SPIRV-Tools/test/opt/dead_branch_elim_test.cpp
Steven Perron 5ce8cf781f
Change the order branches are simplified in dead branch elim (#2728)
Dead branch elimination needs to know about the constructs that a block is contained it when determining what to do with its merge instruction.  We currently fold branches in block as we see them, which is parent constructs before their children.  This causes the struct cfg analysis to crash because it tries to get the parent construct for a block after the parent has been folded.

This can be fixed by folding the branch of the children before the parents.

Fixes #2667.
2019-07-10 14:59:44 -04:00

3168 lines
83 KiB
C++

// Copyright (c) 2017 Valve Corporation
// Copyright (c) 2017 LunarG Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include <string>
#include "test/opt/pass_fixture.h"
#include "test/opt/pass_utils.h"
namespace spvtools {
namespace opt {
namespace {
using DeadBranchElimTest = PassTest<::testing::Test>;
TEST_F(DeadBranchElimTest, IfThenElseTrue) {
// #version 140
//
// in vec4 BaseColor;
//
// void main()
// {
// vec4 v;
// if (true)
// v = vec4(0.0,0.0,0.0,0.0);
// else
// v = vec4(1.0,1.0,1.0,1.0);
// gl_FragColor = v;
// }
const std::string predefs =
R"(OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main" %gl_FragColor %BaseColor
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
OpName %main "main"
OpName %v "v"
OpName %gl_FragColor "gl_FragColor"
OpName %BaseColor "BaseColor"
%void = OpTypeVoid
%7 = OpTypeFunction %void
%bool = OpTypeBool
%true = OpConstantTrue %bool
%float = OpTypeFloat 32
%v4float = OpTypeVector %float 4
%_ptr_Function_v4float = OpTypePointer Function %v4float
%float_0 = OpConstant %float 0
%14 = OpConstantComposite %v4float %float_0 %float_0 %float_0 %float_0
%float_1 = OpConstant %float 1
%16 = OpConstantComposite %v4float %float_1 %float_1 %float_1 %float_1
%_ptr_Output_v4float = OpTypePointer Output %v4float
%gl_FragColor = OpVariable %_ptr_Output_v4float Output
%_ptr_Input_v4float = OpTypePointer Input %v4float
%BaseColor = OpVariable %_ptr_Input_v4float Input
)";
const std::string before =
R"(%main = OpFunction %void None %7
%19 = OpLabel
%v = OpVariable %_ptr_Function_v4float Function
OpSelectionMerge %20 None
OpBranchConditional %true %21 %22
%21 = OpLabel
OpStore %v %14
OpBranch %20
%22 = OpLabel
OpStore %v %16
OpBranch %20
%20 = OpLabel
%23 = OpLoad %v4float %v
OpStore %gl_FragColor %23
OpReturn
OpFunctionEnd
)";
const std::string after =
R"(%main = OpFunction %void None %7
%19 = OpLabel
%v = OpVariable %_ptr_Function_v4float Function
OpBranch %21
%21 = OpLabel
OpStore %v %14
OpBranch %20
%20 = OpLabel
%23 = OpLoad %v4float %v
OpStore %gl_FragColor %23
OpReturn
OpFunctionEnd
)";
SinglePassRunAndCheck<DeadBranchElimPass>(predefs + before, predefs + after,
true, true);
}
TEST_F(DeadBranchElimTest, IfThenElseFalse) {
// #version 140
//
// in vec4 BaseColor;
//
// void main()
// {
// vec4 v;
// if (false)
// v = vec4(0.0,0.0,0.0,0.0);
// else
// v = vec4(1.0,1.0,1.0,1.0);
// gl_FragColor = v;
// }
const std::string predefs =
R"(OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main" %gl_FragColor %BaseColor
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
OpName %main "main"
OpName %v "v"
OpName %gl_FragColor "gl_FragColor"
OpName %BaseColor "BaseColor"
%void = OpTypeVoid
%7 = OpTypeFunction %void
%bool = OpTypeBool
%false = OpConstantFalse %bool
%float = OpTypeFloat 32
%v4float = OpTypeVector %float 4
%_ptr_Function_v4float = OpTypePointer Function %v4float
%float_0 = OpConstant %float 0
%14 = OpConstantComposite %v4float %float_0 %float_0 %float_0 %float_0
%float_1 = OpConstant %float 1
%16 = OpConstantComposite %v4float %float_1 %float_1 %float_1 %float_1
%_ptr_Output_v4float = OpTypePointer Output %v4float
%gl_FragColor = OpVariable %_ptr_Output_v4float Output
%_ptr_Input_v4float = OpTypePointer Input %v4float
%BaseColor = OpVariable %_ptr_Input_v4float Input
)";
const std::string before =
R"(%main = OpFunction %void None %7
%19 = OpLabel
%v = OpVariable %_ptr_Function_v4float Function
OpSelectionMerge %20 None
OpBranchConditional %false %21 %22
%21 = OpLabel
OpStore %v %14
OpBranch %20
%22 = OpLabel
OpStore %v %16
OpBranch %20
%20 = OpLabel
%23 = OpLoad %v4float %v
OpStore %gl_FragColor %23
OpReturn
OpFunctionEnd
)";
const std::string after =
R"(%main = OpFunction %void None %7
%19 = OpLabel
%v = OpVariable %_ptr_Function_v4float Function
OpBranch %22
%22 = OpLabel
OpStore %v %16
OpBranch %20
%20 = OpLabel
%23 = OpLoad %v4float %v
OpStore %gl_FragColor %23
OpReturn
OpFunctionEnd
)";
SinglePassRunAndCheck<DeadBranchElimPass>(predefs + before, predefs + after,
true, true);
}
TEST_F(DeadBranchElimTest, IfThenTrue) {
// #version 140
//
// in vec4 BaseColor;
//
// void main()
// {
// vec4 v = BaseColor;
// if (true)
// v = v * vec4(0.5,0.5,0.5,0.5);
// gl_FragColor = v;
// }
const std::string predefs =
R"(OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main" %BaseColor %gl_FragColor
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
OpName %main "main"
OpName %v "v"
OpName %BaseColor "BaseColor"
OpName %gl_FragColor "gl_FragColor"
%void = OpTypeVoid
%7 = OpTypeFunction %void
%float = OpTypeFloat 32
%v4float = OpTypeVector %float 4
%_ptr_Function_v4float = OpTypePointer Function %v4float
%_ptr_Input_v4float = OpTypePointer Input %v4float
%BaseColor = OpVariable %_ptr_Input_v4float Input
%bool = OpTypeBool
%true = OpConstantTrue %bool
%float_0_5 = OpConstant %float 0.5
%15 = OpConstantComposite %v4float %float_0_5 %float_0_5 %float_0_5 %float_0_5
%_ptr_Output_v4float = OpTypePointer Output %v4float
%gl_FragColor = OpVariable %_ptr_Output_v4float Output
)";
const std::string before =
R"(%main = OpFunction %void None %7
%17 = OpLabel
%v = OpVariable %_ptr_Function_v4float Function
%18 = OpLoad %v4float %BaseColor
OpStore %v %18
OpSelectionMerge %19 None
OpBranchConditional %true %20 %19
%20 = OpLabel
%21 = OpLoad %v4float %v
%22 = OpFMul %v4float %21 %15
OpStore %v %22
OpBranch %19
%19 = OpLabel
%23 = OpLoad %v4float %v
OpStore %gl_FragColor %23
OpReturn
OpFunctionEnd
)";
const std::string after =
R"(%main = OpFunction %void None %7
%17 = OpLabel
%v = OpVariable %_ptr_Function_v4float Function
%18 = OpLoad %v4float %BaseColor
OpStore %v %18
OpBranch %20
%20 = OpLabel
%21 = OpLoad %v4float %v
%22 = OpFMul %v4float %21 %15
OpStore %v %22
OpBranch %19
%19 = OpLabel
%23 = OpLoad %v4float %v
OpStore %gl_FragColor %23
OpReturn
OpFunctionEnd
)";
SinglePassRunAndCheck<DeadBranchElimPass>(predefs + before, predefs + after,
true, true);
}
TEST_F(DeadBranchElimTest, IfThenFalse) {
// #version 140
//
// in vec4 BaseColor;
//
// void main()
// {
// vec4 v = BaseColor;
// if (false)
// v = v * vec4(0.5,0.5,0.5,0.5);
// gl_FragColor = v;
// }
const std::string predefs =
R"(OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main" %BaseColor %gl_FragColor
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
OpName %main "main"
OpName %v "v"
OpName %BaseColor "BaseColor"
OpName %gl_FragColor "gl_FragColor"
%void = OpTypeVoid
%7 = OpTypeFunction %void
%float = OpTypeFloat 32
%v4float = OpTypeVector %float 4
%_ptr_Function_v4float = OpTypePointer Function %v4float
%_ptr_Input_v4float = OpTypePointer Input %v4float
%BaseColor = OpVariable %_ptr_Input_v4float Input
%bool = OpTypeBool
%false = OpConstantFalse %bool
%float_0_5 = OpConstant %float 0.5
%15 = OpConstantComposite %v4float %float_0_5 %float_0_5 %float_0_5 %float_0_5
%_ptr_Output_v4float = OpTypePointer Output %v4float
%gl_FragColor = OpVariable %_ptr_Output_v4float Output
)";
const std::string before =
R"(%main = OpFunction %void None %7
%17 = OpLabel
%v = OpVariable %_ptr_Function_v4float Function
%18 = OpLoad %v4float %BaseColor
OpStore %v %18
OpSelectionMerge %19 None
OpBranchConditional %false %20 %19
%20 = OpLabel
%21 = OpLoad %v4float %v
%22 = OpFMul %v4float %21 %15
OpStore %v %22
OpBranch %19
%19 = OpLabel
%23 = OpLoad %v4float %v
OpStore %gl_FragColor %23
OpReturn
OpFunctionEnd
)";
const std::string after =
R"(%main = OpFunction %void None %7
%17 = OpLabel
%v = OpVariable %_ptr_Function_v4float Function
%18 = OpLoad %v4float %BaseColor
OpStore %v %18
OpBranch %19
%19 = OpLabel
%23 = OpLoad %v4float %v
OpStore %gl_FragColor %23
OpReturn
OpFunctionEnd
)";
SinglePassRunAndCheck<DeadBranchElimPass>(predefs + before, predefs + after,
true, true);
}
TEST_F(DeadBranchElimTest, IfThenElsePhiTrue) {
// Test handling of phi in merge block after dead branch elimination.
// Note: The SPIR-V has had store/load elimination and phi insertion
//
// #version 140
//
// void main()
// {
// vec4 v;
// if (true)
// v = vec4(0.0,0.0,0.0,0.0);
// else
// v = vec4(1.0,1.0,1.0,1.0);
// gl_FragColor = v;
// }
const std::string predefs =
R"(OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main" %gl_FragColor
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
OpName %main "main"
OpName %gl_FragColor "gl_FragColor"
%void = OpTypeVoid
%5 = OpTypeFunction %void
%bool = OpTypeBool
%true = OpConstantTrue %bool
%float = OpTypeFloat 32
%v4float = OpTypeVector %float 4
%_ptr_Function_v4float = OpTypePointer Function %v4float
%float_0 = OpConstant %float 0
%12 = OpConstantComposite %v4float %float_0 %float_0 %float_0 %float_0
%float_1 = OpConstant %float 1
%14 = OpConstantComposite %v4float %float_1 %float_1 %float_1 %float_1
%_ptr_Output_v4float = OpTypePointer Output %v4float
%gl_FragColor = OpVariable %_ptr_Output_v4float Output
%_ptr_Input_v4float = OpTypePointer Input %v4float
)";
const std::string before =
R"(%main = OpFunction %void None %5
%17 = OpLabel
OpSelectionMerge %18 None
OpBranchConditional %true %19 %20
%19 = OpLabel
OpBranch %18
%20 = OpLabel
OpBranch %18
%18 = OpLabel
%21 = OpPhi %v4float %12 %19 %14 %20
OpStore %gl_FragColor %21
OpReturn
OpFunctionEnd
)";
const std::string after =
R"(%main = OpFunction %void None %5
%17 = OpLabel
OpBranch %19
%19 = OpLabel
OpBranch %18
%18 = OpLabel
OpStore %gl_FragColor %12
OpReturn
OpFunctionEnd
)";
SinglePassRunAndCheck<DeadBranchElimPass>(predefs + before, predefs + after,
true, true);
}
TEST_F(DeadBranchElimTest, IfThenElsePhiFalse) {
// Test handling of phi in merge block after dead branch elimination.
// Note: The SPIR-V has had store/load elimination and phi insertion
//
// #version 140
//
// void main()
// {
// vec4 v;
// if (true)
// v = vec4(0.0,0.0,0.0,0.0);
// else
// v = vec4(1.0,1.0,1.0,1.0);
// gl_FragColor = v;
// }
const std::string predefs =
R"(OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main" %gl_FragColor
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
OpName %main "main"
OpName %gl_FragColor "gl_FragColor"
%void = OpTypeVoid
%5 = OpTypeFunction %void
%bool = OpTypeBool
%false = OpConstantFalse %bool
%float = OpTypeFloat 32
%v4float = OpTypeVector %float 4
%_ptr_Function_v4float = OpTypePointer Function %v4float
%float_0 = OpConstant %float 0
%12 = OpConstantComposite %v4float %float_0 %float_0 %float_0 %float_0
%float_1 = OpConstant %float 1
%14 = OpConstantComposite %v4float %float_1 %float_1 %float_1 %float_1
%_ptr_Output_v4float = OpTypePointer Output %v4float
%gl_FragColor = OpVariable %_ptr_Output_v4float Output
%_ptr_Input_v4float = OpTypePointer Input %v4float
)";
const std::string before =
R"(%main = OpFunction %void None %5
%17 = OpLabel
OpSelectionMerge %18 None
OpBranchConditional %false %19 %20
%19 = OpLabel
OpBranch %18
%20 = OpLabel
OpBranch %18
%18 = OpLabel
%21 = OpPhi %v4float %12 %19 %14 %20
OpStore %gl_FragColor %21
OpReturn
OpFunctionEnd
)";
const std::string after =
R"(%main = OpFunction %void None %5
%17 = OpLabel
OpBranch %20
%20 = OpLabel
OpBranch %18
%18 = OpLabel
OpStore %gl_FragColor %14
OpReturn
OpFunctionEnd
)";
SinglePassRunAndCheck<DeadBranchElimPass>(predefs + before, predefs + after,
true, true);
}
TEST_F(DeadBranchElimTest, CompoundIfThenElseFalse) {
// #version 140
//
// layout(std140) uniform U_t
// {
// bool g_B ;
// } ;
//
// void main()
// {
// vec4 v;
// if (false) {
// if (g_B)
// v = vec4(0.0,0.0,0.0,0.0);
// else
// v = vec4(1.0,1.0,1.0,1.0);
// } else {
// if (g_B)
// v = vec4(1.0,1.0,1.0,1.0);
// else
// v = vec4(0.0,0.0,0.0,0.0);
// }
// gl_FragColor = v;
// }
const std::string predefs =
R"(OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main" %gl_FragColor
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
OpName %main "main"
OpName %U_t "U_t"
OpMemberName %U_t 0 "g_B"
OpName %_ ""
OpName %v "v"
OpName %gl_FragColor "gl_FragColor"
OpMemberDecorate %U_t 0 Offset 0
OpDecorate %U_t Block
OpDecorate %_ DescriptorSet 0
%void = OpTypeVoid
%8 = OpTypeFunction %void
%bool = OpTypeBool
%false = OpConstantFalse %bool
%uint = OpTypeInt 32 0
%U_t = OpTypeStruct %uint
%_ptr_Uniform_U_t = OpTypePointer Uniform %U_t
%_ = OpVariable %_ptr_Uniform_U_t Uniform
%int = OpTypeInt 32 1
%int_0 = OpConstant %int 0
%_ptr_Uniform_uint = OpTypePointer Uniform %uint
%uint_0 = OpConstant %uint 0
%float = OpTypeFloat 32
%v4float = OpTypeVector %float 4
%_ptr_Function_v4float = OpTypePointer Function %v4float
%float_0 = OpConstant %float 0
%21 = OpConstantComposite %v4float %float_0 %float_0 %float_0 %float_0
%float_1 = OpConstant %float 1
%23 = OpConstantComposite %v4float %float_1 %float_1 %float_1 %float_1
%_ptr_Output_v4float = OpTypePointer Output %v4float
%gl_FragColor = OpVariable %_ptr_Output_v4float Output
)";
const std::string before =
R"(%main = OpFunction %void None %8
%25 = OpLabel
%v = OpVariable %_ptr_Function_v4float Function
OpSelectionMerge %26 None
OpBranchConditional %false %27 %28
%27 = OpLabel
%29 = OpAccessChain %_ptr_Uniform_uint %_ %int_0
%30 = OpLoad %uint %29
%31 = OpINotEqual %bool %30 %uint_0
OpSelectionMerge %32 None
OpBranchConditional %31 %33 %34
%33 = OpLabel
OpStore %v %21
OpBranch %32
%34 = OpLabel
OpStore %v %23
OpBranch %32
%32 = OpLabel
OpBranch %26
%28 = OpLabel
%35 = OpAccessChain %_ptr_Uniform_uint %_ %int_0
%36 = OpLoad %uint %35
%37 = OpINotEqual %bool %36 %uint_0
OpSelectionMerge %38 None
OpBranchConditional %37 %39 %40
%39 = OpLabel
OpStore %v %23
OpBranch %38
%40 = OpLabel
OpStore %v %21
OpBranch %38
%38 = OpLabel
OpBranch %26
%26 = OpLabel
%41 = OpLoad %v4float %v
OpStore %gl_FragColor %41
OpReturn
OpFunctionEnd
)";
const std::string after =
R"(%main = OpFunction %void None %8
%25 = OpLabel
%v = OpVariable %_ptr_Function_v4float Function
OpBranch %28
%28 = OpLabel
%35 = OpAccessChain %_ptr_Uniform_uint %_ %int_0
%36 = OpLoad %uint %35
%37 = OpINotEqual %bool %36 %uint_0
OpSelectionMerge %38 None
OpBranchConditional %37 %39 %40
%40 = OpLabel
OpStore %v %21
OpBranch %38
%39 = OpLabel
OpStore %v %23
OpBranch %38
%38 = OpLabel
OpBranch %26
%26 = OpLabel
%41 = OpLoad %v4float %v
OpStore %gl_FragColor %41
OpReturn
OpFunctionEnd
)";
SinglePassRunAndCheck<DeadBranchElimPass>(predefs + before, predefs + after,
true, true);
}
TEST_F(DeadBranchElimTest, PreventOrphanMerge) {
const std::string predefs =
R"(OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main" %BaseColor %gl_FragColor
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
OpName %main "main"
OpName %v "v"
OpName %BaseColor "BaseColor"
OpName %gl_FragColor "gl_FragColor"
%void = OpTypeVoid
%7 = OpTypeFunction %void
%float = OpTypeFloat 32
%v4float = OpTypeVector %float 4
%_ptr_Function_v4float = OpTypePointer Function %v4float
%_ptr_Input_v4float = OpTypePointer Input %v4float
%BaseColor = OpVariable %_ptr_Input_v4float Input
%bool = OpTypeBool
%true = OpConstantTrue %bool
%float_0_5 = OpConstant %float 0.5
%_ptr_Output_v4float = OpTypePointer Output %v4float
%gl_FragColor = OpVariable %_ptr_Output_v4float Output
)";
const std::string before =
R"(%main = OpFunction %void None %7
%16 = OpLabel
%v = OpVariable %_ptr_Function_v4float Function
%17 = OpLoad %v4float %BaseColor
OpStore %v %17
OpSelectionMerge %18 None
OpBranchConditional %true %19 %20
%19 = OpLabel
OpKill
%20 = OpLabel
%21 = OpLoad %v4float %v
%22 = OpVectorTimesScalar %v4float %21 %float_0_5
OpStore %v %22
OpBranch %18
%18 = OpLabel
%23 = OpLoad %v4float %v
OpStore %gl_FragColor %23
OpReturn
OpFunctionEnd
)";
const std::string after =
R"(%main = OpFunction %void None %7
%16 = OpLabel
%v = OpVariable %_ptr_Function_v4float Function
%17 = OpLoad %v4float %BaseColor
OpStore %v %17
OpBranch %19
%19 = OpLabel
OpKill
OpFunctionEnd
)";
SinglePassRunAndCheck<DeadBranchElimPass>(predefs + before, predefs + after,
true, true);
}
TEST_F(DeadBranchElimTest, HandleOrphanMerge) {
const std::string predefs =
R"(OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main" %gl_FragColor
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
OpName %main "main"
OpName %foo_ "foo("
OpName %gl_FragColor "gl_FragColor"
OpDecorate %gl_FragColor Location 0
%void = OpTypeVoid
%6 = OpTypeFunction %void
%float = OpTypeFloat 32
%v4float = OpTypeVector %float 4
%9 = OpTypeFunction %v4float
%bool = OpTypeBool
%true = OpConstantTrue %bool
%float_0 = OpConstant %float 0
%13 = OpConstantComposite %v4float %float_0 %float_0 %float_0 %float_0
%float_1 = OpConstant %float 1
%15 = OpConstantComposite %v4float %float_1 %float_1 %float_1 %float_1
%_ptr_Output_v4float = OpTypePointer Output %v4float
%gl_FragColor = OpVariable %_ptr_Output_v4float Output
%main = OpFunction %void None %6
%17 = OpLabel
%18 = OpFunctionCall %v4float %foo_
OpStore %gl_FragColor %18
OpReturn
OpFunctionEnd
)";
const std::string before =
R"(%foo_ = OpFunction %v4float None %9
%19 = OpLabel
OpSelectionMerge %20 None
OpBranchConditional %true %21 %22
%21 = OpLabel
OpReturnValue %13
%22 = OpLabel
OpReturnValue %15
%20 = OpLabel
%23 = OpUndef %v4float
OpReturnValue %23
OpFunctionEnd
)";
const std::string after =
R"(%foo_ = OpFunction %v4float None %9
%19 = OpLabel
OpBranch %21
%21 = OpLabel
OpReturnValue %13
OpFunctionEnd
)";
SinglePassRunAndCheck<DeadBranchElimPass>(predefs + before, predefs + after,
true, true);
}
TEST_F(DeadBranchElimTest, KeepContinueTargetWhenKillAfterMerge) {
// #version 450
// void main() {
// bool c;
// bool d;
// while(c) {
// if(d) {
// continue;
// }
// if(false) {
// continue;
// }
// discard;
// }
// }
const std::string predefs =
R"(OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main"
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 450
OpName %main "main"
OpName %c "c"
OpName %d "d"
%void = OpTypeVoid
%6 = OpTypeFunction %void
%bool = OpTypeBool
%_ptr_Function_bool = OpTypePointer Function %bool
%false = OpConstantFalse %bool
)";
const std::string before =
R"(%main = OpFunction %void None %6
%10 = OpLabel
%c = OpVariable %_ptr_Function_bool Function
%d = OpVariable %_ptr_Function_bool Function
OpBranch %11
%11 = OpLabel
OpLoopMerge %12 %13 None
OpBranch %14
%14 = OpLabel
%15 = OpLoad %bool %c
OpBranchConditional %15 %16 %12
%16 = OpLabel
%17 = OpLoad %bool %d
OpSelectionMerge %18 None
OpBranchConditional %17 %19 %18
%19 = OpLabel
OpBranch %13
%18 = OpLabel
OpSelectionMerge %20 None
OpBranchConditional %false %21 %20
%21 = OpLabel
OpBranch %13
%20 = OpLabel
OpKill
%13 = OpLabel
OpBranch %11
%12 = OpLabel
OpReturn
OpFunctionEnd
)";
const std::string after =
R"(%main = OpFunction %void None %6
%10 = OpLabel
%c = OpVariable %_ptr_Function_bool Function
%d = OpVariable %_ptr_Function_bool Function
OpBranch %11
%11 = OpLabel
OpLoopMerge %12 %13 None
OpBranch %14
%14 = OpLabel
%15 = OpLoad %bool %c
OpBranchConditional %15 %16 %12
%16 = OpLabel
%17 = OpLoad %bool %d
OpSelectionMerge %18 None
OpBranchConditional %17 %19 %18
%19 = OpLabel
OpBranch %13
%18 = OpLabel
OpBranch %20
%20 = OpLabel
OpKill
%13 = OpLabel
OpBranch %11
%12 = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndCheck<DeadBranchElimPass>(predefs + before, predefs + after,
true, true);
}
TEST_F(DeadBranchElimTest, DecorateDeleted) {
// Note: SPIR-V hand-edited to add decoration
// #version 140
//
// in vec4 BaseColor;
//
// void main()
// {
// vec4 v = BaseColor;
// if (false)
// v = v * vec4(0.5,0.5,0.5,0.5);
// gl_FragColor = v;
// }
const std::string predefs_before =
R"(OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main" %BaseColor %gl_FragColor
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
OpName %main "main"
OpName %v "v"
OpName %BaseColor "BaseColor"
OpName %gl_FragColor "gl_FragColor"
OpDecorate %22 RelaxedPrecision
%void = OpTypeVoid
%7 = OpTypeFunction %void
%float = OpTypeFloat 32
%v4float = OpTypeVector %float 4
%_ptr_Function_v4float = OpTypePointer Function %v4float
%_ptr_Input_v4float = OpTypePointer Input %v4float
%BaseColor = OpVariable %_ptr_Input_v4float Input
%bool = OpTypeBool
%false = OpConstantFalse %bool
%float_0_5 = OpConstant %float 0.5
%15 = OpConstantComposite %v4float %float_0_5 %float_0_5 %float_0_5 %float_0_5
%_ptr_Output_v4float = OpTypePointer Output %v4float
%gl_FragColor = OpVariable %_ptr_Output_v4float Output
)";
const std::string predefs_after =
R"(OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main" %BaseColor %gl_FragColor
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
OpName %main "main"
OpName %v "v"
OpName %BaseColor "BaseColor"
OpName %gl_FragColor "gl_FragColor"
%void = OpTypeVoid
%8 = OpTypeFunction %void
%float = OpTypeFloat 32
%v4float = OpTypeVector %float 4
%_ptr_Function_v4float = OpTypePointer Function %v4float
%_ptr_Input_v4float = OpTypePointer Input %v4float
%BaseColor = OpVariable %_ptr_Input_v4float Input
%bool = OpTypeBool
%false = OpConstantFalse %bool
%float_0_5 = OpConstant %float 0.5
%16 = OpConstantComposite %v4float %float_0_5 %float_0_5 %float_0_5 %float_0_5
%_ptr_Output_v4float = OpTypePointer Output %v4float
%gl_FragColor = OpVariable %_ptr_Output_v4float Output
)";
const std::string before =
R"(%main = OpFunction %void None %7
%17 = OpLabel
%v = OpVariable %_ptr_Function_v4float Function
%18 = OpLoad %v4float %BaseColor
OpStore %v %18
OpSelectionMerge %19 None
OpBranchConditional %false %20 %19
%20 = OpLabel
%21 = OpLoad %v4float %v
%22 = OpFMul %v4float %21 %15
OpStore %v %22
OpBranch %19
%19 = OpLabel
%23 = OpLoad %v4float %v
OpStore %gl_FragColor %23
OpReturn
OpFunctionEnd
)";
const std::string after =
R"(%main = OpFunction %void None %8
%18 = OpLabel
%v = OpVariable %_ptr_Function_v4float Function
%19 = OpLoad %v4float %BaseColor
OpStore %v %19
OpBranch %20
%20 = OpLabel
%23 = OpLoad %v4float %v
OpStore %gl_FragColor %23
OpReturn
OpFunctionEnd
)";
SinglePassRunAndCheck<DeadBranchElimPass>(predefs_before + before,
predefs_after + after, true, true);
}
TEST_F(DeadBranchElimTest, LoopInDeadBranch) {
// #version 450
//
// layout(location = 0) in vec4 BaseColor;
// layout(location = 0) out vec4 OutColor;
//
// void main()
// {
// vec4 v = BaseColor;
// if (false)
// for (int i=0; i<3; i++)
// v = v * 0.5;
// OutColor = v;
// }
const std::string predefs =
R"(OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main" %BaseColor %OutColor
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 450
OpName %main "main"
OpName %v "v"
OpName %BaseColor "BaseColor"
OpName %i "i"
OpName %OutColor "OutColor"
OpDecorate %BaseColor Location 0
OpDecorate %OutColor Location 0
%void = OpTypeVoid
%8 = OpTypeFunction %void
%float = OpTypeFloat 32
%v4float = OpTypeVector %float 4
%_ptr_Function_v4float = OpTypePointer Function %v4float
%_ptr_Input_v4float = OpTypePointer Input %v4float
%BaseColor = OpVariable %_ptr_Input_v4float Input
%bool = OpTypeBool
%false = OpConstantFalse %bool
%int = OpTypeInt 32 1
%_ptr_Function_int = OpTypePointer Function %int
%int_0 = OpConstant %int 0
%int_3 = OpConstant %int 3
%float_0_5 = OpConstant %float 0.5
%int_1 = OpConstant %int 1
%_ptr_Output_v4float = OpTypePointer Output %v4float
%OutColor = OpVariable %_ptr_Output_v4float Output
)";
const std::string before =
R"(%main = OpFunction %void None %8
%22 = OpLabel
%v = OpVariable %_ptr_Function_v4float Function
%i = OpVariable %_ptr_Function_int Function
%23 = OpLoad %v4float %BaseColor
OpStore %v %23
OpSelectionMerge %24 None
OpBranchConditional %false %25 %24
%25 = OpLabel
OpStore %i %int_0
OpBranch %26
%26 = OpLabel
OpLoopMerge %27 %28 None
OpBranch %29
%29 = OpLabel
%30 = OpLoad %int %i
%31 = OpSLessThan %bool %30 %int_3
OpBranchConditional %31 %32 %27
%32 = OpLabel
%33 = OpLoad %v4float %v
%34 = OpVectorTimesScalar %v4float %33 %float_0_5
OpStore %v %34
OpBranch %28
%28 = OpLabel
%35 = OpLoad %int %i
%36 = OpIAdd %int %35 %int_1
OpStore %i %36
OpBranch %26
%27 = OpLabel
OpBranch %24
%24 = OpLabel
%37 = OpLoad %v4float %v
OpStore %OutColor %37
OpReturn
OpFunctionEnd
)";
const std::string after =
R"(%main = OpFunction %void None %8
%22 = OpLabel
%v = OpVariable %_ptr_Function_v4float Function
%i = OpVariable %_ptr_Function_int Function
%23 = OpLoad %v4float %BaseColor
OpStore %v %23
OpBranch %24
%24 = OpLabel
%37 = OpLoad %v4float %v
OpStore %OutColor %37
OpReturn
OpFunctionEnd
)";
SinglePassRunAndCheck<DeadBranchElimPass>(predefs + before, predefs + after,
true, true);
}
TEST_F(DeadBranchElimTest, SwitchLiveCase) {
// #version 450
//
// layout (location=0) in vec4 BaseColor;
// layout (location=0) out vec4 OutColor;
//
// void main()
// {
// switch (1) {
// case 0:
// OutColor = vec4(0.0,0.0,0.0,0.0);
// break;
// case 1:
// OutColor = vec4(0.125,0.125,0.125,0.125);
// break;
// case 2:
// OutColor = vec4(0.25,0.25,0.25,0.25);
// break;
// default:
// OutColor = vec4(1.0,1.0,1.0,1.0);
// }
// }
const std::string predefs =
R"(OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main" %OutColor %BaseColor
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 450
OpName %main "main"
OpName %OutColor "OutColor"
OpName %BaseColor "BaseColor"
OpDecorate %OutColor Location 0
OpDecorate %BaseColor Location 0
%void = OpTypeVoid
%6 = OpTypeFunction %void
%int = OpTypeInt 32 1
%int_1 = OpConstant %int 1
%float = OpTypeFloat 32
%v4float = OpTypeVector %float 4
%_ptr_Output_v4float = OpTypePointer Output %v4float
%OutColor = OpVariable %_ptr_Output_v4float Output
%float_0 = OpConstant %float 0
%13 = OpConstantComposite %v4float %float_0 %float_0 %float_0 %float_0
%float_0_125 = OpConstant %float 0.125
%15 = OpConstantComposite %v4float %float_0_125 %float_0_125 %float_0_125 %float_0_125
%float_0_25 = OpConstant %float 0.25
%17 = OpConstantComposite %v4float %float_0_25 %float_0_25 %float_0_25 %float_0_25
%float_1 = OpConstant %float 1
%19 = OpConstantComposite %v4float %float_1 %float_1 %float_1 %float_1
%_ptr_Input_v4float = OpTypePointer Input %v4float
%BaseColor = OpVariable %_ptr_Input_v4float Input
)";
const std::string before =
R"(%main = OpFunction %void None %6
%21 = OpLabel
OpSelectionMerge %22 None
OpSwitch %int_1 %23 0 %24 1 %25 2 %26
%23 = OpLabel
OpStore %OutColor %19
OpBranch %22
%24 = OpLabel
OpStore %OutColor %13
OpBranch %22
%25 = OpLabel
OpStore %OutColor %15
OpBranch %22
%26 = OpLabel
OpStore %OutColor %17
OpBranch %22
%22 = OpLabel
OpReturn
OpFunctionEnd
)";
const std::string after =
R"(%main = OpFunction %void None %6
%21 = OpLabel
OpBranch %25
%25 = OpLabel
OpStore %OutColor %15
OpBranch %22
%22 = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndCheck<DeadBranchElimPass>(predefs + before, predefs + after,
true, true);
}
TEST_F(DeadBranchElimTest, SwitchLiveDefault) {
// #version 450
//
// layout (location=0) in vec4 BaseColor;
// layout (location=0) out vec4 OutColor;
//
// void main()
// {
// switch (7) {
// case 0:
// OutColor = vec4(0.0,0.0,0.0,0.0);
// break;
// case 1:
// OutColor = vec4(0.125,0.125,0.125,0.125);
// break;
// case 2:
// OutColor = vec4(0.25,0.25,0.25,0.25);
// break;
// default:
// OutColor = vec4(1.0,1.0,1.0,1.0);
// }
// }
const std::string predefs =
R"(OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main" %OutColor %BaseColor
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 450
OpName %main "main"
OpName %OutColor "OutColor"
OpName %BaseColor "BaseColor"
OpDecorate %OutColor Location 0
OpDecorate %BaseColor Location 0
%void = OpTypeVoid
%6 = OpTypeFunction %void
%int = OpTypeInt 32 1
%int_7 = OpConstant %int 7
%float = OpTypeFloat 32
%v4float = OpTypeVector %float 4
%_ptr_Output_v4float = OpTypePointer Output %v4float
%OutColor = OpVariable %_ptr_Output_v4float Output
%float_0 = OpConstant %float 0
%13 = OpConstantComposite %v4float %float_0 %float_0 %float_0 %float_0
%float_0_125 = OpConstant %float 0.125
%15 = OpConstantComposite %v4float %float_0_125 %float_0_125 %float_0_125 %float_0_125
%float_0_25 = OpConstant %float 0.25
%17 = OpConstantComposite %v4float %float_0_25 %float_0_25 %float_0_25 %float_0_25
%float_1 = OpConstant %float 1
%19 = OpConstantComposite %v4float %float_1 %float_1 %float_1 %float_1
%_ptr_Input_v4float = OpTypePointer Input %v4float
%BaseColor = OpVariable %_ptr_Input_v4float Input
)";
const std::string before =
R"(%main = OpFunction %void None %6
%21 = OpLabel
OpSelectionMerge %22 None
OpSwitch %int_7 %23 0 %24 1 %25 2 %26
%23 = OpLabel
OpStore %OutColor %19
OpBranch %22
%24 = OpLabel
OpStore %OutColor %13
OpBranch %22
%25 = OpLabel
OpStore %OutColor %15
OpBranch %22
%26 = OpLabel
OpStore %OutColor %17
OpBranch %22
%22 = OpLabel
OpReturn
OpFunctionEnd
)";
const std::string after =
R"(%main = OpFunction %void None %6
%21 = OpLabel
OpBranch %23
%23 = OpLabel
OpStore %OutColor %19
OpBranch %22
%22 = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndCheck<DeadBranchElimPass>(predefs + before, predefs + after,
true, true);
}
TEST_F(DeadBranchElimTest, SwitchLiveCaseBreakFromLoop) {
// This sample does not directly translate to GLSL/HLSL as
// direct breaks from a loop cannot be made from a switch.
// This construct is currently formed by inlining a function
// containing early returns from the cases of a switch. The
// function is wrapped in a one-trip loop and returns are
// translated to branches to the loop's merge block.
const std::string predefs =
R"(OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main" %OutColor %BaseColor
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 450
OpName %main "main"
OpName %oc "oc"
OpName %OutColor "OutColor"
OpName %BaseColor "BaseColor"
OpDecorate %OutColor Location 0
OpDecorate %BaseColor Location 0
%void = OpTypeVoid
%7 = OpTypeFunction %void
%bool = OpTypeBool
%true = OpConstantTrue %bool
%false = OpConstantFalse %bool
%int = OpTypeInt 32 1
%int_1 = OpConstant %int 1
%float = OpTypeFloat 32
%v4float = OpTypeVector %float 4
%_ptr_Function_v4float = OpTypePointer Function %v4float
%float_0 = OpConstant %float 0
%17 = OpConstantComposite %v4float %float_0 %float_0 %float_0 %float_0
%float_0_125 = OpConstant %float 0.125
%19 = OpConstantComposite %v4float %float_0_125 %float_0_125 %float_0_125 %float_0_125
%float_0_25 = OpConstant %float 0.25
%21 = OpConstantComposite %v4float %float_0_25 %float_0_25 %float_0_25 %float_0_25
%float_1 = OpConstant %float 1
%23 = OpConstantComposite %v4float %float_1 %float_1 %float_1 %float_1
%_ptr_Output_v4float = OpTypePointer Output %v4float
%OutColor = OpVariable %_ptr_Output_v4float Output
%_ptr_Input_v4float = OpTypePointer Input %v4float
%BaseColor = OpVariable %_ptr_Input_v4float Input
)";
const std::string before =
R"(%main = OpFunction %void None %7
%26 = OpLabel
%oc = OpVariable %_ptr_Function_v4float Function
OpBranch %27
%27 = OpLabel
OpLoopMerge %28 %29 None
OpBranch %30
%30 = OpLabel
OpSelectionMerge %31 None
OpSwitch %int_1 %31 0 %32 1 %33 2 %34
%32 = OpLabel
OpStore %oc %17
OpBranch %28
%33 = OpLabel
OpStore %oc %19
OpBranch %28
%34 = OpLabel
OpStore %oc %21
OpBranch %28
%31 = OpLabel
OpStore %oc %23
OpBranch %28
%29 = OpLabel
OpBranchConditional %false %27 %28
%28 = OpLabel
%35 = OpLoad %v4float %oc
OpStore %OutColor %35
OpReturn
OpFunctionEnd
)";
const std::string after =
R"(%main = OpFunction %void None %7
%26 = OpLabel
%oc = OpVariable %_ptr_Function_v4float Function
OpBranch %27
%27 = OpLabel
OpLoopMerge %28 %29 None
OpBranch %30
%30 = OpLabel
OpBranch %33
%33 = OpLabel
OpStore %oc %19
OpBranch %28
%29 = OpLabel
OpBranch %27
%28 = OpLabel
%35 = OpLoad %v4float %oc
OpStore %OutColor %35
OpReturn
OpFunctionEnd
)";
SinglePassRunAndCheck<DeadBranchElimPass>(predefs + before, predefs + after,
true, true);
}
TEST_F(DeadBranchElimTest, LeaveContinueBackedge) {
const std::string text = R"(
; CHECK: OpLoopMerge [[merge:%\w+]] [[continue:%\w+]] None
; CHECK: [[continue]] = OpLabel
; CHECK-NEXT: OpBranchConditional {{%\w+}} {{%\w+}} [[merge]]
; CHECK-NEXT: [[merge]] = OpLabel
; CHECK-NEXT: OpReturn
OpCapability Kernel
OpCapability Linkage
OpMemoryModel Logical OpenCL
%bool = OpTypeBool
%false = OpConstantFalse %bool
%void = OpTypeVoid
%funcTy = OpTypeFunction %void
%func = OpFunction %void None %funcTy
%1 = OpLabel
OpBranch %2
%2 = OpLabel
OpLoopMerge %3 %4 None
OpBranch %4
%4 = OpLabel
; Be careful we don't remove the backedge to %2 despite never taking it.
OpBranchConditional %false %2 %3
%3 = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(text, true);
}
TEST_F(DeadBranchElimTest, LeaveContinueBackedgeExtraBlock) {
const std::string text = R"(
; CHECK: OpBranch [[header:%\w+]]
; CHECK: OpLoopMerge [[merge:%\w+]] [[continue:%\w+]] None
; CHECK-NEXT: OpBranch [[continue]]
; CHECK-NEXT: [[continue]] = OpLabel
; CHECK-NEXT: OpBranchConditional {{%\w+}} [[extra:%\w+]] [[merge]]
; CHECK-NEXT: [[extra]] = OpLabel
; CHECK-NEXT: OpBranch [[header]]
; CHECK-NEXT: [[merge]] = OpLabel
; CHECK-NEXT: OpReturn
OpCapability Kernel
OpCapability Linkage
OpMemoryModel Logical OpenCL
%bool = OpTypeBool
%false = OpConstantFalse %bool
%void = OpTypeVoid
%funcTy = OpTypeFunction %void
%func = OpFunction %void None %funcTy
%1 = OpLabel
OpBranch %2
%2 = OpLabel
OpLoopMerge %3 %4 None
OpBranch %4
%4 = OpLabel
; Be careful we don't remove the backedge to %2 despite never taking it.
OpBranchConditional %false %5 %3
; This block remains live despite being unreachable.
%5 = OpLabel
OpBranch %2
%3 = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(text, true);
}
TEST_F(DeadBranchElimTest, RemovePhiWithUnreachableContinue) {
const std::string text = R"(
; CHECK: [[entry:%\w+]] = OpLabel
; CHECK-NEXT: OpBranch [[header:%\w+]]
; CHECK: OpLoopMerge [[merge:%\w+]] [[continue:%\w+]] None
; CHECK-NEXT: OpBranch [[ret:%\w+]]
; CHECK-NEXT: [[ret]] = OpLabel
; CHECK-NEXT: OpReturn
; CHECK: [[continue]] = OpLabel
; CHECK-NEXT: OpBranch [[header]]
; CHECK: [[merge]] = OpLabel
; CHECK-NEXT: OpUnreachable
OpCapability Kernel
OpCapability Linkage
OpMemoryModel Logical OpenCL
OpName %func "func"
OpDecorate %func LinkageAttributes "func" Export
%bool = OpTypeBool
%false = OpConstantFalse %bool
%true = OpConstantTrue %bool
%void = OpTypeVoid
%funcTy = OpTypeFunction %void
%func = OpFunction %void None %funcTy
%1 = OpLabel
OpBranch %2
%2 = OpLabel
%phi = OpPhi %bool %false %1 %true %continue
OpLoopMerge %merge %continue None
OpBranch %3
%3 = OpLabel
OpReturn
%continue = OpLabel
OpBranch %2
%merge = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(text, true);
}
TEST_F(DeadBranchElimTest, UnreachableLoopMergeAndContinueTargets) {
const std::string text = R"(
; CHECK: [[undef:%\w+]] = OpUndef %bool
; CHECK: OpSelectionMerge [[header:%\w+]]
; CHECK-NEXT: OpBranchConditional {{%\w+}} [[if_lab:%\w+]] [[else_lab:%\w+]]
; CHECK: OpPhi %bool %false [[if_lab]] %false [[else_lab]] [[undef]] [[continue:%\w+]]
; CHECK-NEXT: OpLoopMerge [[merge:%\w+]] [[continue]] None
; CHECK-NEXT: OpBranch [[ret:%\w+]]
; CHECK-NEXT: [[ret]] = OpLabel
; CHECK-NEXT: OpReturn
; CHECK: [[continue]] = OpLabel
; CHECK-NEXT: OpBranch [[header]]
; CHECK: [[merge]] = OpLabel
; CHECK-NEXT: OpUnreachable
OpCapability Kernel
OpCapability Linkage
OpMemoryModel Logical OpenCL
OpName %func "func"
OpDecorate %func LinkageAttributes "func" Export
%bool = OpTypeBool
%false = OpConstantFalse %bool
%true = OpConstantTrue %bool
%void = OpTypeVoid
%funcTy = OpTypeFunction %void
%func = OpFunction %void None %funcTy
%1 = OpLabel
%c = OpUndef %bool
OpSelectionMerge %2 None
OpBranchConditional %c %if %else
%if = OpLabel
OpBranch %2
%else = OpLabel
OpBranch %2
%2 = OpLabel
%phi = OpPhi %bool %false %if %false %else %true %continue
OpLoopMerge %merge %continue None
OpBranch %3
%3 = OpLabel
OpReturn
%continue = OpLabel
OpBranch %2
%merge = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(text, true);
}
TEST_F(DeadBranchElimTest, EarlyReconvergence) {
const std::string text = R"(
; CHECK-NOT: OpBranchConditional
; CHECK: [[logical:%\w+]] = OpLogicalOr
; CHECK-NOT: OpPhi
; CHECK: OpLogicalAnd {{%\w+}} {{%\w+}} [[logical]]
OpCapability Shader
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %func "func"
OpExecutionMode %func OriginUpperLeft
%void = OpTypeVoid
%bool = OpTypeBool
%false = OpConstantFalse %bool
%true = OpConstantTrue %bool
%func_ty = OpTypeFunction %void
%func = OpFunction %void None %func_ty
%1 = OpLabel
OpSelectionMerge %2 None
OpBranchConditional %false %3 %4
%3 = OpLabel
%12 = OpLogicalNot %bool %true
OpBranch %2
%4 = OpLabel
OpSelectionMerge %14 None
OpBranchConditional %false %5 %6
%5 = OpLabel
%10 = OpLogicalAnd %bool %true %false
OpBranch %7
%6 = OpLabel
%11 = OpLogicalOr %bool %true %false
OpBranch %7
%7 = OpLabel
; This phi is in a block preceeding the merge %14!
%8 = OpPhi %bool %10 %5 %11 %6
OpBranch %14
%14 = OpLabel
OpBranch %2
%2 = OpLabel
%9 = OpPhi %bool %12 %3 %8 %14
%13 = OpLogicalAnd %bool %true %9
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(text, true);
}
TEST_F(DeadBranchElimTest, RemoveUnreachableBlocksFloating) {
const std::string text = R"(
; CHECK: OpFunction
; CHECK-NEXT: OpLabel
; CHECK-NEXT: OpReturn
; CHECK-NEXT: OpFunctionEnd
OpCapability Kernel
OpCapability Linkage
OpMemoryModel Logical OpenCL
OpName %func "func"
OpDecorate %func LinkageAttributes "func" Export
%void = OpTypeVoid
%1 = OpTypeFunction %void
%func = OpFunction %void None %1
%2 = OpLabel
OpReturn
%3 = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(text, true);
}
TEST_F(DeadBranchElimTest, RemoveUnreachableBlocksFloatingJoin) {
const std::string text = R"(
; CHECK: OpFunction
; CHECK-NEXT: OpFunctionParameter
; CHECK-NEXT: OpLabel
; CHECK-NEXT: OpReturn
; CHECK-NEXT: OpFunctionEnd
OpCapability Kernel
OpCapability Linkage
OpMemoryModel Logical OpenCL
OpName %func "func"
OpDecorate %func LinkageAttributes "func" Export
%void = OpTypeVoid
%bool = OpTypeBool
%false = OpConstantFalse %bool
%true = OpConstantTrue %bool
%1 = OpTypeFunction %void %bool
%func = OpFunction %void None %1
%bool_param = OpFunctionParameter %bool
%2 = OpLabel
OpReturn
%3 = OpLabel
OpSelectionMerge %6 None
OpBranchConditional %bool_param %4 %5
%4 = OpLabel
OpBranch %6
%5 = OpLabel
OpBranch %6
%6 = OpLabel
%7 = OpPhi %bool %true %4 %false %6
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(text, true);
}
TEST_F(DeadBranchElimTest, RemoveUnreachableBlocksDeadPhi) {
const std::string text = R"(
; CHECK: OpFunction
; CHECK-NEXT: OpFunctionParameter
; CHECK-NEXT: OpLabel
; CHECK-NEXT: OpBranch [[label:%\w+]]
; CHECK-NEXT: [[label]] = OpLabel
; CHECK-NEXT: OpLogicalNot %bool %true
; CHECK-NEXT: OpReturn
; CHECK-NEXT: OpFunctionEnd
OpCapability Kernel
OpCapability Linkage
OpMemoryModel Logical OpenCL
OpName %func "func"
OpDecorate %func LinkageAttributes "func" Export
%void = OpTypeVoid
%bool = OpTypeBool
%false = OpConstantFalse %bool
%true = OpConstantTrue %bool
%1 = OpTypeFunction %void %bool
%func = OpFunction %void None %1
%bool_param = OpFunctionParameter %bool
%2 = OpLabel
OpBranch %3
%4 = OpLabel
OpBranch %3
%3 = OpLabel
%5 = OpPhi %bool %true %2 %false %4
%6 = OpLogicalNot %bool %5
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(text, true);
}
TEST_F(DeadBranchElimTest, RemoveUnreachableBlocksPartiallyDeadPhi) {
const std::string text = R"(
; CHECK: OpFunction
; CHECK-NEXT: [[param:%\w+]] = OpFunctionParameter
; CHECK-NEXT: OpLabel
; CHECK-NEXT: OpBranchConditional [[param]] [[merge:%\w+]] [[br:%\w+]]
; CHECK-NEXT: [[merge]] = OpLabel
; CHECK-NEXT: [[phi:%\w+]] = OpPhi %bool %true %2 %false [[br]]
; CHECK-NEXT: OpLogicalNot %bool [[phi]]
; CHECK-NEXT: OpReturn
; CHECK-NEXT: [[br]] = OpLabel
; CHECK-NEXT: OpBranch [[merge]]
; CHECK-NEXT: OpFunctionEnd
OpCapability Kernel
OpCapability Linkage
OpMemoryModel Logical OpenCL
OpName %func "func"
OpDecorate %func LinkageAttributes "func" Export
%void = OpTypeVoid
%bool = OpTypeBool
%false = OpConstantFalse %bool
%true = OpConstantTrue %bool
%1 = OpTypeFunction %void %bool
%func = OpFunction %void None %1
%bool_param = OpFunctionParameter %bool
%2 = OpLabel
OpBranchConditional %bool_param %3 %7
%7 = OpLabel
OpBranch %3
%4 = OpLabel
OpBranch %3
%3 = OpLabel
%5 = OpPhi %bool %true %2 %false %7 %false %4
%6 = OpLogicalNot %bool %5
OpReturn
OpFunctionEnd
)";
SetAssembleOptions(SPV_TEXT_TO_BINARY_OPTION_PRESERVE_NUMERIC_IDS);
SinglePassRunAndMatch<DeadBranchElimPass>(text, true);
}
TEST_F(DeadBranchElimTest, LiveHeaderDeadPhi) {
const std::string text = R"(
; CHECK: OpLabel
; CHECK-NOT: OpBranchConditional
; CHECK-NOT: OpPhi
; CHECK: OpLogicalNot %bool %false
OpCapability Kernel
OpCapability Linkage
OpMemoryModel Logical OpenCL
OpName %func "func"
OpDecorate %func LinkageAttributes "func" Export
%void = OpTypeVoid
%bool = OpTypeBool
%true = OpConstantTrue %bool
%false = OpConstantFalse %bool
%func_ty = OpTypeFunction %void
%func = OpFunction %void None %func_ty
%1 = OpLabel
OpSelectionMerge %3 None
OpBranchConditional %true %2 %3
%2 = OpLabel
OpBranch %3
%3 = OpLabel
%5 = OpPhi %bool %true %3 %false %2
%6 = OpLogicalNot %bool %5
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(text, true);
}
TEST_F(DeadBranchElimTest, ExtraBackedgeBlocksLive) {
const std::string text = R"(
; CHECK: [[entry:%\w+]] = OpLabel
; CHECK-NOT: OpSelectionMerge
; CHECK: OpBranch [[header:%\w+]]
; CHECK-NEXT: [[header]] = OpLabel
; CHECK-NEXT: OpPhi %bool %true [[entry]] %false [[backedge:%\w+]]
; CHECK-NEXT: OpLoopMerge
OpCapability Kernel
OpCapability Linkage
OpMemoryModel Logical OpenCL
OpName %func "func"
OpDecorate %func LinkageAttributes "func" Export
%void = OpTypeVoid
%bool = OpTypeBool
%true = OpConstantTrue %bool
%false = OpConstantFalse %bool
%func_ty = OpTypeFunction %void %bool
%func = OpFunction %void None %func_ty
%param = OpFunctionParameter %bool
%entry = OpLabel
OpSelectionMerge %if_merge None
; This dead branch is included to ensure the pass does work.
OpBranchConditional %false %if_merge %loop_header
%loop_header = OpLabel
; Both incoming edges are live, so the phi should be untouched.
%phi = OpPhi %bool %true %entry %false %backedge
OpLoopMerge %loop_merge %continue None
OpBranchConditional %param %loop_merge %continue
%continue = OpLabel
OpBranch %backedge
%backedge = OpLabel
OpBranch %loop_header
%loop_merge = OpLabel
OpBranch %if_merge
%if_merge = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(text, true);
}
TEST_F(DeadBranchElimTest, ExtraBackedgeBlocksUnreachable) {
const std::string text = R"(
; CHECK: [[entry:%\w+]] = OpLabel
; CHECK-NEXT: OpBranch [[header:%\w+]]
; CHECK-NEXT: [[header]] = OpLabel
; CHECK-NEXT: OpLoopMerge [[merge:%\w+]] [[continue:%\w+]] None
; CHECK-NEXT: OpBranch [[merge]]
; CHECK-NEXT: [[merge]] = OpLabel
; CHECK-NEXT: OpReturn
; CHECK-NEXT: [[continue]] = OpLabel
; CHECK-NEXT: OpBranch [[header]]
OpCapability Kernel
OpCapability Linkage
OpMemoryModel Logical OpenCL
OpName %func "func"
OpDecorate %func LinkageAttributes "func" Export
%void = OpTypeVoid
%bool = OpTypeBool
%true = OpConstantTrue %bool
%false = OpConstantFalse %bool
%func_ty = OpTypeFunction %void %bool
%func = OpFunction %void None %func_ty
%param = OpFunctionParameter %bool
%entry = OpLabel
OpBranch %loop_header
%loop_header = OpLabel
; Since the continue is unreachable, %backedge will be removed. The phi will
; instead require an edge from %continue.
%phi = OpPhi %bool %true %entry %false %backedge
OpLoopMerge %merge %continue None
OpBranch %merge
%continue = OpLabel
OpBranch %backedge
%backedge = OpLabel
OpBranch %loop_header
%merge = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(text, true);
}
TEST_F(DeadBranchElimTest, NoUnnecessaryChanges) {
const std::string text = R"(
OpCapability Shader
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %func "func"
%void = OpTypeVoid
%bool = OpTypeBool
%true = OpConstantTrue %bool
%undef = OpUndef %bool
%functy = OpTypeFunction %void
%func = OpFunction %void None %functy
%1 = OpLabel
OpBranch %2
%2 = OpLabel
OpLoopMerge %4 %5 None
OpBranch %6
%6 = OpLabel
OpReturn
%5 = OpLabel
OpBranch %2
%4 = OpLabel
OpUnreachable
OpFunctionEnd
)";
auto result = SinglePassRunToBinary<DeadBranchElimPass>(text, true);
EXPECT_EQ(std::get<1>(result), Pass::Status::SuccessWithoutChange);
}
TEST_F(DeadBranchElimTest, ExtraBackedgePartiallyDead) {
const std::string text = R"(
; CHECK: OpLabel
; CHECK: [[header:%\w+]] = OpLabel
; CHECK: OpLoopMerge [[merge:%\w+]] [[continue:%\w+]] None
; CHECK: [[merge]] = OpLabel
; CHECK: [[continue]] = OpLabel
; CHECK: OpBranch [[extra:%\w+]]
; CHECK: [[extra]] = OpLabel
; CHECK-NOT: OpSelectionMerge
; CHECK-NEXT: OpBranch [[else:%\w+]]
; CHECK-NEXT: [[else]] = OpLabel
; CHECK-NEXT: OpLogicalOr
; CHECK-NEXT: OpBranch [[backedge:%\w+]]
; CHECK-NEXT: [[backedge:%\w+]] = OpLabel
; CHECK-NEXT: OpBranch [[header]]
OpCapability Kernel
OpCapability Linkage
OpMemoryModel Logical OpenCL
OpName %func "func"
OpDecorate %func LinkageAttributes "func" Export
%void = OpTypeVoid
%bool = OpTypeBool
%true = OpConstantTrue %bool
%false = OpConstantFalse %bool
%func_ty = OpTypeFunction %void %bool
%func = OpFunction %void None %func_ty
%param = OpFunctionParameter %bool
%entry = OpLabel
OpBranch %loop_header
%loop_header = OpLabel
OpLoopMerge %loop_merge %continue None
OpBranchConditional %param %loop_merge %continue
%continue = OpLabel
OpBranch %extra
%extra = OpLabel
OpSelectionMerge %backedge None
OpBranchConditional %false %then %else
%then = OpLabel
%and = OpLogicalAnd %bool %true %false
OpBranch %backedge
%else = OpLabel
%or = OpLogicalOr %bool %true %false
OpBranch %backedge
%backedge = OpLabel
OpBranch %loop_header
%loop_merge = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(text, true);
}
TEST_F(DeadBranchElimTest, UnreachableContinuePhiInMerge) {
const std::string text = R"(
; CHECK: [[entry:%\w+]] = OpLabel
; CHECK-NEXT: OpBranch [[header:%\w+]]
; CHECK-NEXT: [[header]] = OpLabel
; CHECK-NEXT: OpLoopMerge [[merge:%\w+]] [[continue:%\w+]] None
; CHECK-NEXT: OpBranch [[label:%\w+]]
; CHECK-NEXT: [[label]] = OpLabel
; CHECK-NEXT: [[fadd:%\w+]] = OpFAdd
; CHECK-NEXT: OpBranch [[label:%\w+]]
; CHECK-NEXT: [[label]] = OpLabel
; CHECK-NEXT: OpBranch [[merge]]
; CHECK-NEXT: [[continue]] = OpLabel
; CHECK-NEXT: OpBranch [[header]]
; CHECK-NEXT: [[merge]] = OpLabel
; CHECK-NEXT: OpStore {{%\w+}} [[fadd]]
OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main" %o
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 430
OpSourceExtension "GL_GOOGLE_cpp_style_line_directive"
OpSourceExtension "GL_GOOGLE_include_directive"
OpName %main "main"
OpName %o "o"
OpName %S "S"
OpMemberName %S 0 "a"
OpName %U_t "U_t"
OpMemberName %U_t 0 "g_F"
OpMemberName %U_t 1 "g_F2"
OpDecorate %o Location 0
OpMemberDecorate %S 0 Offset 0
OpMemberDecorate %U_t 0 Volatile
OpMemberDecorate %U_t 0 Offset 0
OpMemberDecorate %U_t 1 Offset 4
OpDecorate %U_t BufferBlock
%void = OpTypeVoid
%7 = OpTypeFunction %void
%float = OpTypeFloat 32
%_ptr_Function_float = OpTypePointer Function %float
%float_0 = OpConstant %float 0
%int = OpTypeInt 32 1
%_ptr_Function_int = OpTypePointer Function %int
%int_0 = OpConstant %int 0
%int_10 = OpConstant %int 10
%bool = OpTypeBool
%true = OpConstantTrue %bool
%float_1 = OpConstant %float 1
%float_5 = OpConstant %float 5
%int_1 = OpConstant %int 1
%_ptr_Output_float = OpTypePointer Output %float
%o = OpVariable %_ptr_Output_float Output
%S = OpTypeStruct %float
%U_t = OpTypeStruct %S %S
%_ptr_Uniform_U_t = OpTypePointer Uniform %U_t
%main = OpFunction %void None %7
%22 = OpLabel
OpBranch %23
%23 = OpLabel
%24 = OpPhi %float %float_0 %22 %25 %26
%27 = OpPhi %int %int_0 %22 %28 %26
OpLoopMerge %29 %26 None
OpBranch %40
%40 = OpLabel
%25 = OpFAdd %float %24 %float_1
OpSelectionMerge %30 None
OpBranchConditional %true %31 %30
%31 = OpLabel
OpBranch %29
%30 = OpLabel
OpBranch %26
%26 = OpLabel
%28 = OpIAdd %int %27 %int_1
%32 = OpSLessThan %bool %27 %int_10
; continue block branches to the header or another none dead block.
OpBranchConditional %32 %23 %29
%29 = OpLabel
%33 = OpPhi %float %24 %26 %25 %31
OpStore %o %33
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(text, true);
}
TEST_F(DeadBranchElimTest, NonStructuredIf) {
const std::string text = R"(
; CHECK-NOT: OpBranchConditional
OpCapability Kernel
OpCapability Linkage
OpMemoryModel Logical OpenCL
OpDecorate %func LinkageAttributes "func" Export
%void = OpTypeVoid
%bool = OpTypeBool
%true = OpConstantTrue %bool
%functy = OpTypeFunction %void
%func = OpFunction %void None %functy
%entry = OpLabel
OpBranchConditional %true %then %else
%then = OpLabel
OpBranch %final
%else = OpLabel
OpBranch %final
%final = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(text, true);
}
TEST_F(DeadBranchElimTest, ReorderBlocks) {
const std::string text = R"(
; CHECK: OpLabel
; CHECK: OpBranch [[label:%\w+]]
; CHECK: [[label:%\w+]] = OpLabel
; CHECK-NEXT: OpLogicalNot
; CHECK-NEXT: OpBranch [[label:%\w+]]
; CHECK: [[label]] = OpLabel
; CHECK-NEXT: OpReturn
OpCapability Shader
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %func "func"
OpExecutionMode %func OriginUpperLeft
%void = OpTypeVoid
%bool = OpTypeBool
%true = OpConstantTrue %bool
%func_ty = OpTypeFunction %void
%func = OpFunction %void None %func_ty
%1 = OpLabel
OpSelectionMerge %3 None
OpBranchConditional %true %2 %3
%3 = OpLabel
OpReturn
%2 = OpLabel
%not = OpLogicalNot %bool %true
OpBranch %3
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(text, true);
}
TEST_F(DeadBranchElimTest, ReorderBlocksMultiple) {
// Checks are not important. The validation post optimization is the
// important part.
const std::string text = R"(
; CHECK: OpLabel
OpCapability Shader
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %func "func"
OpExecutionMode %func OriginUpperLeft
%void = OpTypeVoid
%bool = OpTypeBool
%true = OpConstantTrue %bool
%func_ty = OpTypeFunction %void
%func = OpFunction %void None %func_ty
%1 = OpLabel
OpSelectionMerge %3 None
OpBranchConditional %true %2 %3
%3 = OpLabel
OpReturn
%2 = OpLabel
OpBranch %4
%4 = OpLabel
OpBranch %3
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(text, true);
}
TEST_F(DeadBranchElimTest, ReorderBlocksMultiple2) {
// Checks are not important. The validation post optimization is the
// important part.
const std::string text = R"(
; CHECK: OpLabel
OpCapability Shader
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %func "func"
OpExecutionMode %func OriginUpperLeft
%void = OpTypeVoid
%bool = OpTypeBool
%true = OpConstantTrue %bool
%func_ty = OpTypeFunction %void
%func = OpFunction %void None %func_ty
%1 = OpLabel
OpSelectionMerge %3 None
OpBranchConditional %true %2 %3
%3 = OpLabel
OpBranch %5
%5 = OpLabel
OpReturn
%2 = OpLabel
OpBranch %4
%4 = OpLabel
OpBranch %3
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(text, true);
}
TEST_F(DeadBranchElimTest, SelectionMergeWithEarlyExit1) {
// Checks that if a selection merge construct contains a conditional branch
// to the merge node, then the OpSelectionMerge instruction is positioned
// correctly.
const std::string predefs = R"(
OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main"
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
%void = OpTypeVoid
%func_type = OpTypeFunction %void
%bool = OpTypeBool
%true = OpConstantTrue %bool
%undef_bool = OpUndef %bool
)";
const std::string body =
R"(
; CHECK: OpFunction
; CHECK-NEXT: OpLabel
; CHECK-NEXT: OpBranch [[taken_branch:%\w+]]
; CHECK-NEXT: [[taken_branch]] = OpLabel
; CHECK-NEXT: OpSelectionMerge [[merge:%\w+]]
; CHECK-NEXT: OpBranchConditional {{%\w+}} [[merge]] {{%\w+}}
%main = OpFunction %void None %func_type
%entry_bb = OpLabel
OpSelectionMerge %outer_merge None
OpBranchConditional %true %bb1 %bb3
%bb1 = OpLabel
OpBranchConditional %undef_bool %outer_merge %bb2
%bb2 = OpLabel
OpBranch %outer_merge
%bb3 = OpLabel
OpBranch %outer_merge
%outer_merge = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(predefs + body, true);
}
TEST_F(DeadBranchElimTest, SelectionMergeWithEarlyExit2) {
// Checks that if a selection merge construct contains a conditional branch
// to the merge node, then the OpSelectionMerge instruction is positioned
// correctly.
const std::string predefs = R"(
OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main"
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
%void = OpTypeVoid
%func_type = OpTypeFunction %void
%bool = OpTypeBool
%true = OpConstantTrue %bool
%undef_bool = OpUndef %bool
)";
const std::string body =
R"(
; CHECK: OpFunction
; CHECK-NEXT: OpLabel
; CHECK-NEXT: OpBranch [[bb1:%\w+]]
; CHECK-NEXT: [[bb1]] = OpLabel
; CHECK-NEXT: OpSelectionMerge [[inner_merge:%\w+]]
; CHECK: [[inner_merge]] = OpLabel
; CHECK-NEXT: OpSelectionMerge [[outer_merge:%\w+]]
; CHECK-NEXT: OpBranchConditional {{%\w+}} [[outer_merge]:%\w+]] {{%\w+}}
; CHECK: [[outer_merge]] = OpLabel
; CHECK-NEXT: OpReturn
%main = OpFunction %void None %func_type
%entry_bb = OpLabel
OpSelectionMerge %outer_merge None
OpBranchConditional %true %bb1 %bb5
%bb1 = OpLabel
OpSelectionMerge %inner_merge None
OpBranchConditional %undef_bool %bb2 %bb3
%bb2 = OpLabel
OpBranch %inner_merge
%bb3 = OpLabel
OpBranch %inner_merge
%inner_merge = OpLabel
OpBranchConditional %undef_bool %outer_merge %bb4
%bb4 = OpLabel
OpBranch %outer_merge
%bb5 = OpLabel
OpBranch %outer_merge
%outer_merge = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(predefs + body, true);
}
TEST_F(DeadBranchElimTest, SelectionMergeWithConditionalExit) {
// Checks that if a selection merge construct contains a conditional branch
// to the merge node, then we keep the OpSelectionMerge on that branch.
const std::string predefs = R"(
OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main"
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
%void = OpTypeVoid
%func_type = OpTypeFunction %void
%bool = OpTypeBool
%true = OpConstantTrue %bool
%uint = OpTypeInt 32 0
%undef_int = OpUndef %uint
)";
const std::string body =
R"(
; CHECK: OpLoopMerge [[loop_merge:%\w+]]
; CHECK-NEXT: OpBranch [[bb1:%\w+]]
; CHECK: [[bb1]] = OpLabel
; CHECK-NEXT: OpBranch [[bb2:%\w+]]
; CHECK: [[bb2]] = OpLabel
; CHECK-NEXT: OpSelectionMerge [[sel_merge:%\w+]] None
; CHECK-NEXT: OpSwitch {{%\w+}} [[sel_merge]] 1 [[bb3:%\w+]]
; CHECK: [[bb3]] = OpLabel
; CHECK-NEXT: OpBranch [[sel_merge]]
; CHECK: [[sel_merge]] = OpLabel
; CHECK-NEXT: OpBranch [[loop_merge]]
; CHECK: [[loop_merge]] = OpLabel
; CHECK-NEXT: OpReturn
%main = OpFunction %void None %func_type
%entry_bb = OpLabel
OpBranch %loop_header
%loop_header = OpLabel
OpLoopMerge %loop_merge %cont None
OpBranch %bb1
%bb1 = OpLabel
OpSelectionMerge %sel_merge None
OpBranchConditional %true %bb2 %bb4
%bb2 = OpLabel
OpSwitch %undef_int %sel_merge 1 %bb3
%bb3 = OpLabel
OpBranch %sel_merge
%bb4 = OpLabel
OpBranch %sel_merge
%sel_merge = OpLabel
OpBranch %loop_merge
%cont = OpLabel
OpBranch %loop_header
%loop_merge = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(predefs + body, true);
}
TEST_F(DeadBranchElimTest, SelectionMergeWithExitToLoop) {
// Checks that if a selection merge construct contains a conditional branch
// to a loop surrounding the selection merge, then we do not keep the
// OpSelectionMerge instruction.
const std::string predefs = R"(
OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main"
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
%void = OpTypeVoid
%func_type = OpTypeFunction %void
%bool = OpTypeBool
%true = OpConstantTrue %bool
%undef_bool = OpUndef %bool
)";
const std::string body =
R"(
; CHECK: OpLoopMerge [[loop_merge:%\w+]]
; CHECK-NEXT: OpBranch [[bb1:%\w+]]
; CHECK: [[bb1]] = OpLabel
; CHECK-NEXT: OpBranch [[bb2:%\w+]]
; CHECK: [[bb2]] = OpLabel
; CHECK-NEXT: OpBranchConditional {{%\w+}} [[bb3:%\w+]] [[loop_merge]]
; CHECK: [[bb3]] = OpLabel
; CHECK-NEXT: OpBranch [[sel_merge:%\w+]]
; CHECK: [[sel_merge]] = OpLabel
; CHECK-NEXT: OpBranch [[loop_merge]]
; CHECK: [[loop_merge]] = OpLabel
; CHECK-NEXT: OpReturn
%main = OpFunction %void None %func_type
%entry_bb = OpLabel
OpBranch %loop_header
%loop_header = OpLabel
OpLoopMerge %loop_merge %cont None
OpBranch %bb1
%bb1 = OpLabel
OpSelectionMerge %sel_merge None
OpBranchConditional %true %bb2 %bb4
%bb2 = OpLabel
OpBranchConditional %undef_bool %bb3 %loop_merge
%bb3 = OpLabel
OpBranch %sel_merge
%bb4 = OpLabel
OpBranch %sel_merge
%sel_merge = OpLabel
OpBranch %loop_merge
%cont = OpLabel
OpBranch %loop_header
%loop_merge = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(predefs + body, true);
}
TEST_F(DeadBranchElimTest, SelectionMergeWithExitToLoopContinue) {
// Checks that if a selection merge construct contains a conditional branch
// to continue of a loop surrounding the selection merge, then we do not keep
// the OpSelectionMerge instruction.
const std::string predefs = R"(
OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main"
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
%void = OpTypeVoid
%func_type = OpTypeFunction %void
%bool = OpTypeBool
%true = OpConstantTrue %bool
%undef_bool = OpUndef %bool
)";
const std::string body =
R"(;
; CHECK: OpLabel
; CHECK: [[loop_header:%\w+]] = OpLabel
; CHECK: OpLoopMerge [[loop_merge:%\w+]] [[loop_cont:%\w+]]
; CHECK-NEXT: OpBranch [[bb1:%\w+]]
; CHECK: [[bb1]] = OpLabel
; CHECK-NEXT: OpBranch [[bb2:%\w+]]
; CHECK: [[bb2]] = OpLabel
; CHECK-NEXT: OpBranchConditional {{%\w+}} [[bb3:%\w+]] [[loop_cont]]
; CHECK: [[bb3]] = OpLabel
; CHECK-NEXT: OpBranch [[sel_merge:%\w+]]
; CHECK: [[sel_merge]] = OpLabel
; CHECK-NEXT: OpBranch [[loop_merge]]
; CHECK: [[loop_cont]] = OpLabel
; CHECK-NEXT: OpBranch [[loop_header]]
; CHECK: [[loop_merge]] = OpLabel
; CHECK-NEXT: OpReturn
%main = OpFunction %void None %func_type
%entry_bb = OpLabel
OpBranch %loop_header
%loop_header = OpLabel
OpLoopMerge %loop_merge %cont None
OpBranch %bb1
%bb1 = OpLabel
OpSelectionMerge %sel_merge None
OpBranchConditional %true %bb2 %bb4
%bb2 = OpLabel
OpBranchConditional %undef_bool %bb3 %cont
%bb3 = OpLabel
OpBranch %sel_merge
%bb4 = OpLabel
OpBranch %sel_merge
%sel_merge = OpLabel
OpBranch %loop_merge
%cont = OpLabel
OpBranch %loop_header
%loop_merge = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(predefs + body, true);
}
TEST_F(DeadBranchElimTest, SelectionMergeWithExitToLoop2) {
// Same as |SelectionMergeWithExitToLoop|, except the switch goes to the loop
// merge or the selection merge. In this case, we do not need an
// OpSelectionMerge either.
const std::string predefs = R"(
OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main"
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
%void = OpTypeVoid
%func_type = OpTypeFunction %void
%bool = OpTypeBool
%true = OpConstantTrue %bool
%undef_bool = OpUndef %bool
)";
const std::string body =
R"(
; CHECK: OpLoopMerge [[loop_merge:%\w+]]
; CHECK-NEXT: OpBranch [[bb1:%\w+]]
; CHECK: [[bb1]] = OpLabel
; CHECK-NEXT: OpBranch [[bb2:%\w+]]
; CHECK: [[bb2]] = OpLabel
; CHECK-NEXT: OpBranchConditional {{%\w+}} [[sel_merge:%\w+]] [[loop_merge]]
; CHECK: [[sel_merge]] = OpLabel
; CHECK-NEXT: OpBranch [[loop_merge]]
; CHECK: [[loop_merge]] = OpLabel
; CHECK-NEXT: OpReturn
%main = OpFunction %void None %func_type
%entry_bb = OpLabel
OpBranch %loop_header
%loop_header = OpLabel
OpLoopMerge %loop_merge %cont None
OpBranch %bb1
%bb1 = OpLabel
OpSelectionMerge %sel_merge None
OpBranchConditional %true %bb2 %bb4
%bb2 = OpLabel
OpBranchConditional %undef_bool %sel_merge %loop_merge
%bb4 = OpLabel
OpBranch %sel_merge
%sel_merge = OpLabel
OpBranch %loop_merge
%cont = OpLabel
OpBranch %loop_header
%loop_merge = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(predefs + body, true);
}
TEST_F(DeadBranchElimTest, SelectionMergeWithExitToLoopContinue2) {
// Same as |SelectionMergeWithExitToLoopContinue|, except the branch goes to
// the loop continue or the selection merge. In this case, we do not need an
// OpSelectionMerge either.
const std::string predefs = R"(
OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main"
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
%void = OpTypeVoid
%func_type = OpTypeFunction %void
%bool = OpTypeBool
%true = OpConstantTrue %bool
%undef_bool = OpUndef %bool
)";
const std::string body =
R"(
; CHECK: OpLabel
; CHECK: [[loop_header:%\w+]] = OpLabel
; CHECK: OpLoopMerge [[loop_merge:%\w+]] [[loop_cont:%\w+]]
; CHECK-NEXT: OpBranch [[bb1:%\w+]]
; CHECK: [[bb1]] = OpLabel
; CHECK-NEXT: OpBranch [[bb2:%\w+]]
; CHECK: [[bb2]] = OpLabel
; CHECK-NEXT: OpBranchConditional {{%\w+}} [[sel_merge:%\w+]] [[loop_cont]]
; CHECK: [[sel_merge]] = OpLabel
; CHECK-NEXT: OpBranch [[loop_merge]]
; CHECK: [[loop_cont]] = OpLabel
; CHECK: OpBranch [[loop_header]]
; CHECK: [[loop_merge]] = OpLabel
; CHECK-NEXT: OpReturn
%main = OpFunction %void None %func_type
%entry_bb = OpLabel
OpBranch %loop_header
%loop_header = OpLabel
OpLoopMerge %loop_merge %cont None
OpBranch %bb1
%bb1 = OpLabel
OpSelectionMerge %sel_merge None
OpBranchConditional %true %bb2 %bb4
%bb2 = OpLabel
OpBranchConditional %undef_bool %sel_merge %cont
%bb4 = OpLabel
OpBranch %sel_merge
%sel_merge = OpLabel
OpBranch %loop_merge
%cont = OpLabel
OpBranch %loop_header
%loop_merge = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(predefs + body, true);
}
TEST_F(DeadBranchElimTest, SelectionMergeWithExitToLoop3) {
// Checks that if a selection merge construct contains a conditional branch
// to the merge of a surrounding loop, the selection merge, and another block
// inside the selection merge, then we must keep the OpSelectionMerge
// instruction on that branch.
const std::string predefs = R"(
OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main"
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
%void = OpTypeVoid
%func_type = OpTypeFunction %void
%bool = OpTypeBool
%true = OpConstantTrue %bool
%uint = OpTypeInt 32 0
%undef_int = OpUndef %uint
)";
const std::string body =
R"(
; CHECK: OpLoopMerge [[loop_merge:%\w+]]
; CHECK-NEXT: OpBranch [[bb1:%\w+]]
; CHECK: [[bb1]] = OpLabel
; CHECK-NEXT: OpBranch [[bb2:%\w+]]
; CHECK: [[bb2]] = OpLabel
; CHECK-NEXT: OpSelectionMerge [[sel_merge:%\w+]] None
; CHECK-NEXT: OpSwitch {{%\w+}} [[sel_merge]] 0 [[loop_merge]] 1 [[bb3:%\w+]]
; CHECK: [[bb3]] = OpLabel
; CHECK-NEXT: OpBranch [[sel_merge]]
; CHECK: [[sel_merge]] = OpLabel
; CHECK-NEXT: OpBranch [[loop_merge]]
; CHECK: [[loop_merge]] = OpLabel
; CHECK-NEXT: OpReturn
%main = OpFunction %void None %func_type
%entry_bb = OpLabel
OpBranch %loop_header
%loop_header = OpLabel
OpLoopMerge %loop_merge %cont None
OpBranch %bb1
%bb1 = OpLabel
OpSelectionMerge %sel_merge None
OpBranchConditional %true %bb2 %bb4
%bb2 = OpLabel
OpSwitch %undef_int %sel_merge 0 %loop_merge 1 %bb3
%bb3 = OpLabel
OpBranch %sel_merge
%bb4 = OpLabel
OpBranch %sel_merge
%sel_merge = OpLabel
OpBranch %loop_merge
%cont = OpLabel
OpBranch %loop_header
%loop_merge = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(predefs + body, true);
}
TEST_F(DeadBranchElimTest, SelectionMergeWithExitToLoopContinue3) {
// Checks that if a selection merge construct contains a conditional branch
// to the merge of a surrounding loop, the selection merge, and another block
// inside the selection merge, then we must keep the OpSelectionMerge
// instruction on that branch.
const std::string predefs = R"(
OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main"
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
%void = OpTypeVoid
%func_type = OpTypeFunction %void
%bool = OpTypeBool
%true = OpConstantTrue %bool
%uint = OpTypeInt 32 0
%undef_int = OpUndef %uint
)";
const std::string body =
R"(
; CHECK: OpLabel
; CHECK: [[loop_header:%\w+]] = OpLabel
; CHECK: OpLoopMerge [[loop_merge:%\w+]] [[loop_continue:%\w+]]
; CHECK-NEXT: OpBranch [[bb1:%\w+]]
; CHECK: [[bb1]] = OpLabel
; CHECK-NEXT: OpBranch [[bb2:%\w+]]
; CHECK: [[bb2]] = OpLabel
; CHECK-NEXT: OpSelectionMerge [[sel_merge:%\w+]] None
; CHECK-NEXT: OpSwitch {{%\w+}} [[sel_merge]] 0 [[loop_continue]] 1 [[bb3:%\w+]]
; CHECK: [[bb3]] = OpLabel
; CHECK-NEXT: OpBranch [[sel_merge]]
; CHECK: [[sel_merge]] = OpLabel
; CHECK-NEXT: OpBranch [[loop_merge]]
; CHECK: [[loop_continue]] = OpLabel
; CHECK-NEXT: OpBranch [[loop_header]]
; CHECK: [[loop_merge]] = OpLabel
; CHECK-NEXT: OpReturn
%main = OpFunction %void None %func_type
%entry_bb = OpLabel
OpBranch %loop_header
%loop_header = OpLabel
OpLoopMerge %loop_merge %cont None
OpBranch %bb1
%bb1 = OpLabel
OpSelectionMerge %sel_merge None
OpBranchConditional %true %bb2 %bb4
%bb2 = OpLabel
OpSwitch %undef_int %sel_merge 0 %cont 1 %bb3
%bb3 = OpLabel
OpBranch %sel_merge
%bb4 = OpLabel
OpBranch %sel_merge
%sel_merge = OpLabel
OpBranch %loop_merge
%cont = OpLabel
OpBranch %loop_header
%loop_merge = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(predefs + body, true);
}
TEST_F(DeadBranchElimTest, SelectionMergeWithExitToLoop4) {
// Same as |SelectionMergeWithExitToLoop|, except the branch in the selection
// construct is an |OpSwitch| instead of an |OpConditionalBranch|. The
// OpSelectionMerge instruction is not needed in this case either.
const std::string predefs = R"(
OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main"
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
%void = OpTypeVoid
%func_type = OpTypeFunction %void
%bool = OpTypeBool
%true = OpConstantTrue %bool
%uint = OpTypeInt 32 0
%undef_int = OpUndef %uint
)";
const std::string body =
R"(
; CHECK: OpLoopMerge [[loop_merge:%\w+]]
; CHECK-NEXT: OpBranch [[bb1:%\w+]]
; CHECK: [[bb1]] = OpLabel
; CHECK-NEXT: OpBranch [[bb2:%\w+]]
; CHECK: [[bb2]] = OpLabel
; CHECK-NEXT: OpSwitch {{%\w+}} [[bb3:%\w+]] 0 [[loop_merge]] 1 [[bb3:%\w+]]
; CHECK: [[bb3]] = OpLabel
; CHECK-NEXT: OpBranch [[sel_merge:%\w+]]
; CHECK: [[sel_merge]] = OpLabel
; CHECK-NEXT: OpBranch [[loop_merge]]
; CHECK: [[loop_merge]] = OpLabel
; CHECK-NEXT: OpReturn
%main = OpFunction %void None %func_type
%entry_bb = OpLabel
OpBranch %loop_header
%loop_header = OpLabel
OpLoopMerge %loop_merge %cont None
OpBranch %bb1
%bb1 = OpLabel
OpSelectionMerge %sel_merge None
OpBranchConditional %true %bb2 %bb4
%bb2 = OpLabel
OpSwitch %undef_int %bb3 0 %loop_merge 1 %bb3
%bb3 = OpLabel
OpBranch %sel_merge
%bb4 = OpLabel
OpBranch %sel_merge
%sel_merge = OpLabel
OpBranch %loop_merge
%cont = OpLabel
OpBranch %loop_header
%loop_merge = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(predefs + body, true);
}
TEST_F(DeadBranchElimTest, SelectionMergeWithExitToLoopContinue4) {
// Same as |SelectionMergeWithExitToLoopContinue|, except the branch in the
// selection construct is an |OpSwitch| instead of an |OpConditionalBranch|.
// The OpSelectionMerge instruction is not needed in this case either.
const std::string predefs = R"(
OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main"
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
%void = OpTypeVoid
%func_type = OpTypeFunction %void
%bool = OpTypeBool
%true = OpConstantTrue %bool
%uint = OpTypeInt 32 0
%undef_int = OpUndef %uint
)";
const std::string body =
R"(
; CHECK: OpLoopMerge [[loop_merge:%\w+]] [[loop_cont:%\w+]]
; CHECK-NEXT: OpBranch [[bb1:%\w+]]
; CHECK: [[bb1]] = OpLabel
; CHECK-NEXT: OpBranch [[bb2:%\w+]]
; CHECK: [[bb2]] = OpLabel
; CHECK-NEXT: OpSwitch {{%\w+}} [[bb3:%\w+]] 0 [[loop_cont]] 1 [[bb3:%\w+]]
; CHECK: [[bb3]] = OpLabel
; CHECK-NEXT: OpBranch [[sel_merge:%\w+]]
; CHECK: [[sel_merge]] = OpLabel
; CHECK-NEXT: OpBranch [[loop_merge]]
; CHECK: [[loop_merge]] = OpLabel
; CHECK-NEXT: OpReturn
%main = OpFunction %void None %func_type
%entry_bb = OpLabel
OpBranch %loop_header
%loop_header = OpLabel
OpLoopMerge %loop_merge %cont None
OpBranch %bb1
%bb1 = OpLabel
OpSelectionMerge %sel_merge None
OpBranchConditional %true %bb2 %bb4
%bb2 = OpLabel
OpSwitch %undef_int %bb3 0 %cont 1 %bb3
%bb3 = OpLabel
OpBranch %sel_merge
%bb4 = OpLabel
OpBranch %sel_merge
%sel_merge = OpLabel
OpBranch %loop_merge
%cont = OpLabel
OpBranch %loop_header
%loop_merge = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(predefs + body, true);
}
TEST_F(DeadBranchElimTest, SelectionMergeSameAsLoopContinue) {
// Same as |SelectionMergeWithExitToLoopContinue|, except the branch in the
// selection construct is an |OpSwitch| instead of an |OpConditionalBranch|.
// The OpSelectionMerge instruction is not needed in this case either.
const std::string predefs = R"(
OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main"
OpExecutionMode %main OriginUpperLeft
OpSource GLSL 140
%void = OpTypeVoid
%func_type = OpTypeFunction %void
%bool = OpTypeBool
%true = OpConstantTrue %bool
%uint = OpTypeInt 32 0
%undef_bool = OpUndef %bool
)";
const std::string body =
R"(
; CHECK: OpLabel
; CHECK: [[loop_header:%\w+]] = OpLabel
; CHECK: OpLoopMerge [[loop_merge:%\w+]] [[loop_cont:%\w+]]
; CHECK-NEXT: OpBranch [[bb1:%\w+]]
; CHECK: [[bb1]] = OpLabel
; CHECK-NEXT: OpBranch [[bb2:%\w+]]
; CHECK: [[bb2]] = OpLabel
; CHECK-NEXT: OpSelectionMerge [[loop_cont]]
; CHECK-NEXT: OpBranchConditional {{%\w+}} [[bb3:%\w+]] [[loop_cont]]
; CHECK: [[bb3]] = OpLabel
; CHECK-NEXT: OpBranch [[loop_cont]]
; CHECK: [[loop_cont]] = OpLabel
; CHECK-NEXT: OpBranchConditional {{%\w+}} [[loop_header]] [[loop_merge]]
; CHECK: [[loop_merge]] = OpLabel
; CHECK-NEXT: OpReturn
%main = OpFunction %void None %func_type
%entry_bb = OpLabel
OpBranch %loop_header
%loop_header = OpLabel
OpLoopMerge %loop_merge %cont None
OpBranch %bb1
%bb1 = OpLabel
OpSelectionMerge %cont None
OpBranchConditional %true %bb2 %bb4
%bb2 = OpLabel
OpBranchConditional %undef_bool %bb3 %cont
%bb3 = OpLabel
OpBranch %cont
%bb4 = OpLabel
OpBranch %cont
%cont = OpLabel
OpBranchConditional %undef_bool %loop_header %loop_merge
%loop_merge = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(predefs + body, true);
}
TEST_F(DeadBranchElimTest, SelectionMergeWithNestedLoop) {
const std::string body =
R"(
; CHECK: OpSelectionMerge [[merge1:%\w+]]
; CHECK: [[merge1]] = OpLabel
; CHECK-NEXT: OpBranch [[preheader:%\w+]]
; CHECK: [[preheader]] = OpLabel
; CHECK-NOT: OpLabel
; CHECK: OpBranch [[header:%\w+]]
; CHECK: [[header]] = OpLabel
; CHECK-NOT: OpLabel
; CHECK: OpLoopMerge [[merge2:%\w+]]
; CHECK: [[merge2]] = OpLabel
; CHECK-NEXT: OpUnreachable
OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main"
OpExecutionMode %main OriginUpperLeft
OpSource ESSL 310
OpName %main "main"
OpName %h "h"
OpName %i "i"
%void = OpTypeVoid
%3 = OpTypeFunction %void
%bool = OpTypeBool
%_ptr_Function_bool = OpTypePointer Function %bool
%true = OpConstantTrue %bool
%int = OpTypeInt 32 1
%_ptr_Function_int = OpTypePointer Function %int
%int_1 = OpConstant %int 1
%int_0 = OpConstant %int 0
%27 = OpUndef %bool
%main = OpFunction %void None %3
%5 = OpLabel
%h = OpVariable %_ptr_Function_bool Function
%i = OpVariable %_ptr_Function_int Function
OpSelectionMerge %11 None
OpBranchConditional %27 %10 %11
%10 = OpLabel
OpBranch %11
%11 = OpLabel
OpSelectionMerge %14 None
OpBranchConditional %true %13 %14
%13 = OpLabel
OpStore %i %int_1
OpBranch %19
%19 = OpLabel
OpLoopMerge %21 %22 None
OpBranch %23
%23 = OpLabel
%26 = OpSGreaterThan %bool %int_1 %int_0
OpBranchConditional %true %20 %21
%20 = OpLabel
OpBranch %22
%22 = OpLabel
OpBranch %19
%21 = OpLabel
OpBranch %14
%14 = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(body, true);
}
TEST_F(DeadBranchElimTest, DontFoldBackedge) {
const std::string body =
R"(OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %2 "main"
OpExecutionMode %2 OriginUpperLeft
%void = OpTypeVoid
%4 = OpTypeFunction %void
%bool = OpTypeBool
%false = OpConstantFalse %bool
%2 = OpFunction %void None %4
%7 = OpLabel
OpBranch %8
%8 = OpLabel
OpLoopMerge %9 %10 None
OpBranch %11
%11 = OpLabel
%12 = OpUndef %bool
OpSelectionMerge %10 None
OpBranchConditional %12 %13 %10
%13 = OpLabel
OpBranch %9
%10 = OpLabel
OpBranch %14
%14 = OpLabel
OpBranchConditional %false %8 %9
%9 = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndCheck<DeadBranchElimPass>(body, body, true);
}
TEST_F(DeadBranchElimTest, FoldBackedgeToHeader) {
const std::string body =
R"(
; CHECK: OpLabel
; CHECK: [[header:%\w+]] = OpLabel
; CHECK-NEXT: OpLoopMerge {{%\w+}} [[cont:%\w+]]
; CHECK: [[cont]] = OpLabel
; This branch may not be in the continue block, but must come after it.
; CHECK: OpBranch [[header]]
OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %2 "main"
OpExecutionMode %2 OriginUpperLeft
%void = OpTypeVoid
%4 = OpTypeFunction %void
%bool = OpTypeBool
%true = OpConstantTrue %bool
%2 = OpFunction %void None %4
%7 = OpLabel
OpBranch %8
%8 = OpLabel
OpLoopMerge %9 %10 None
OpBranch %11
%11 = OpLabel
%12 = OpUndef %bool
OpSelectionMerge %10 None
OpBranchConditional %12 %13 %10
%13 = OpLabel
OpBranch %9
%10 = OpLabel
OpBranch %14
%14 = OpLabel
OpBranchConditional %true %8 %9
%9 = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(body, true);
}
TEST_F(DeadBranchElimTest, UnreachableMergeAndContinueSameBlock) {
const std::string spirv = R"(
; CHECK: OpLabel
; CHECK: [[outer:%\w+]] = OpLabel
; CHECK-NEXT: OpLoopMerge [[outer_merge:%\w+]] [[outer_cont:%\w+]] None
; CHECK-NEXT: OpBranch [[inner:%\w+]]
; CHECK: [[inner]] = OpLabel
; CHECK: OpLoopMerge [[outer_cont]] [[inner_cont:%\w+]] None
; CHECK: [[inner_cont]] = OpLabel
; CHECK-NEXT: OpBranch [[inner]]
; CHECK: [[outer_cont]] = OpLabel
; CHECK-NEXT: OpBranch [[outer]]
; CHECK: [[outer_merge]] = OpLabel
; CHECK-NEXT: OpUnreachable
OpCapability Shader
OpMemoryModel Logical GLSL450
OpEntryPoint GLCompute %main "main"
OpExecutionMode %main LocalSize 1 1 1
%void = OpTypeVoid
%bool = OpTypeBool
%true = OpConstantTrue %bool
%void_fn = OpTypeFunction %void
%main = OpFunction %void None %void_fn
%entry = OpLabel
OpBranch %outer_loop
%outer_loop = OpLabel
OpLoopMerge %outer_merge %outer_continue None
OpBranch %inner_loop
%inner_loop = OpLabel
OpLoopMerge %outer_continue %inner_continue None
OpBranch %inner_body
%inner_body = OpLabel
OpSelectionMerge %inner_continue None
OpBranchConditional %true %ret %inner_continue
%ret = OpLabel
OpReturn
%inner_continue = OpLabel
OpBranchConditional %true %outer_continue %inner_loop
%outer_continue = OpLabel
OpBranchConditional %true %outer_merge %outer_loop
%outer_merge = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(spirv, true);
}
// Fold a switch with a nested break. The only case should be the default.
TEST_F(DeadBranchElimTest, FoldSwitchWithNestedBreak) {
const std::string spirv = R"(
; CHECK: OpSwitch %int_3 [[case_bb:%\w+]]{{[[:space:]]}}
; CHECK: [[case_bb]] = OpLabel
; CHECK-NEXT: OpUndef
; CHECK-NEXT: OpSelectionMerge
OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Vertex %2 "main"
OpSource GLSL 450
%void = OpTypeVoid
%4 = OpTypeFunction %void
%int = OpTypeInt 32 1
%_ptr_Function_int = OpTypePointer Function %int
%int_3 = OpConstant %int 3
%int_1 = OpConstant %int 1
%bool = OpTypeBool
%2 = OpFunction %void None %4
%10 = OpLabel
OpSelectionMerge %11 None
OpSwitch %int_3 %12 3 %13
%12 = OpLabel
OpBranch %11
%13 = OpLabel
%14 = OpUndef %bool
OpSelectionMerge %15 None
OpBranchConditional %14 %16 %15
%16 = OpLabel
OpBranch %11
%15 = OpLabel
OpBranch %11
%11 = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(spirv, true);
}
TEST_F(DeadBranchElimTest, FoldBranchWithBreakToSwitch) {
const std::string spirv = R"(
; CHECK: OpSelectionMerge [[sel_merge:%\w+]]
; CHECK-NEXT: OpSwitch {{%\w+}} {{%\w+}} 3 [[bb:%\w+]]
; CHECK: [[bb]] = OpLabel
; CHECK-NEXT: OpBranch [[bb2:%\w+]]
; CHECK: [[bb2]] = OpLabel
; CHECK-NOT: OpSelectionMerge
; CHECK: OpFunctionEnd
OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Vertex %2 "main"
OpSource GLSL 450
%void = OpTypeVoid
%4 = OpTypeFunction %void
%int = OpTypeInt 32 1
%_ptr_Function_int = OpTypePointer Function %int
%int_3 = OpConstant %int 3
%int_1 = OpConstant %int 1
%bool = OpTypeBool
%true = OpConstantTrue %bool
%2 = OpFunction %void None %4
%10 = OpLabel
%undef_int = OpUndef %int
OpSelectionMerge %11 None
OpSwitch %undef_int %12 3 %13
%12 = OpLabel
OpBranch %11
%13 = OpLabel
OpSelectionMerge %15 None
OpBranchConditional %true %16 %15
%16 = OpLabel
%14 = OpUndef %bool
OpBranchConditional %14 %11 %17
%17 = OpLabel
OpBranch %15
%15 = OpLabel
OpBranch %11
%11 = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndMatch<DeadBranchElimPass>(spirv, true);
}
TEST_F(DeadBranchElimTest, IfInSwitch) {
// #version 310 es
//
// void main()
// {
// switch(0)
// {
// case 0:
// if(false)
// {
// }
// else
// {
// }
// }
// }
const std::string before =
R"(OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main"
OpExecutionMode %main OriginUpperLeft
OpSource ESSL 310
OpName %main "main"
%void = OpTypeVoid
%3 = OpTypeFunction %void
%int = OpTypeInt 32 1
%int_0 = OpConstant %int 0
%bool = OpTypeBool
%false = OpConstantFalse %bool
%main = OpFunction %void None %3
%5 = OpLabel
OpSelectionMerge %9 None
OpSwitch %int_0 %9 0 %8
%8 = OpLabel
OpSelectionMerge %13 None
OpBranchConditional %false %12 %13
%12 = OpLabel
OpBranch %13
%13 = OpLabel
OpBranch %9
%9 = OpLabel
OpReturn
OpFunctionEnd
)";
const std::string after =
R"(OpCapability Shader
%1 = OpExtInstImport "GLSL.std.450"
OpMemoryModel Logical GLSL450
OpEntryPoint Fragment %main "main"
OpExecutionMode %main OriginUpperLeft
OpSource ESSL 310
OpName %main "main"
%void = OpTypeVoid
%4 = OpTypeFunction %void
%int = OpTypeInt 32 1
%int_0 = OpConstant %int 0
%bool = OpTypeBool
%false = OpConstantFalse %bool
%main = OpFunction %void None %4
%9 = OpLabel
OpBranch %11
%11 = OpLabel
OpBranch %12
%12 = OpLabel
OpBranch %10
%10 = OpLabel
OpReturn
OpFunctionEnd
)";
SinglePassRunAndCheck<DeadBranchElimPass>(before, after, true, true);
}
// TODO(greg-lunarg): Add tests to verify handling of these cases:
//
// More complex control flow
// Others?
} // namespace
} // namespace opt
} // namespace spvtools