Fix dangling phi bug from loop-unroll
When unrolling the following loop:
```
%const0 = OpConstant ...
%const1 = OpConstant ...
...
%LoopHeader = OpLabel
%phi0 = OpPhi %float %const0 %PreHeader %phi1 %Latch
%phi1 = OpPhi %float %const1 %PreHeader %x %Latch
...
%LoopBody = OpLabel
%x = OpFSub %float %phi1 %phi0
...
```
the loop-unroll pass sets the value of `%phi0` as `%phi1` for the second
copy of the loop body. For example, the second copy of
`%x = OpFSub %float %phi1 %phi0` will be
`%y = OpFSub %float %x %phi1`.
Since all phi instructions for inductions will are removed after the
loop unrolling, `%phi1` will be a dead dangling phi.
It happens only for the phi values of the first loop iteration. Replacing those
dangling phis with their initial values fixes this issue.
For example, the second copy of `%x = OpFSub %float %phi1 %phi0` should be
`%y = OpFSub %float %x %const1` because the value of `%phi1` from the
first loop iteration is `%const1`.
This pass converts an internal form of GLSLstd450 Interpolate ops
to the externally valid form. The external form takes the lvalue
of the interpolant. The internal form can do a load of the interpolant.
The pass replaces the load with its pointer. The internal form is
generated by glslang and possibly other frontends for HLSL shaders.
The new pass is called as part of HLSL legalization after all
propagation is complete.
Also adds internal interpolate form to pre-legalization validation
This allows the GPU-AV layer to differentiate between errors with
uniform buffers versus storage buffers and map these to the relevant
VUIDs.
This is a resubmit of a previously reverted commit. The revert was
done as someone erroneously attempted to build the latest validation
layers with a TOT spirv-tools. The validation layers must be built with
their known-good glslang and its known-good spirv-tools and spirv-headers.
* Mark module as modified if convert-to-half removes decorations.
If the convert-to-half pass does not change the body of the function,
but removes decorations, it returns that nothing changed. This is
incorrect, and will be fixed.
Fixes https://github.com/KhronosGroup/SPIRV-Tools/issues/4117
* Update comment for RemoveDecorationsFrom
The existing spirv-opt `DebugInfoManager::AddDebugValueForDecl()` sets
the scope and line info of the new added DebugValue using the scope and
line of DebugDeclare. This is wrong because only a single DebugDeclare
must exist under a scope while we have to add DebugValue for all the
places where the variable's value is updated. Therefore, we have to set
the scope and line of DebugValue based on the places of the variable
updates.
This bug makes
https://github.com/google/amber/blob/main/tests/cases/debugger_hlsl_shadowed_vars.amber
fail. This commit fixes the bug.
Propagating the OpLine/OpNoLine to preserve the debug information
through transformations results in integrity check failures because of
the extra line instructions. This commit lets spirv-opt skip the
integrity check when the code contains OpLine or OpNoLine.
When there is an array of strutured buffers, desc sroa will only split
the array, but not a struct type in the structured buffer. However,
the calcualtion of the number of binding a struct requires does not take
this into consideration. This commit will fix that.
The eliminate dead member pass is written assuming that the index to an
OpAccessChain will be a 32-bit integer or 64-bit integer. That is
changed to work for any width 64-bits or less.
Fixes https://crbug.com/1151727
This instruments ImageRead, ImageWrite and ImageFetch when applied to
texel buffers.
Also add new (but not yet generated) buffer OOB error codes differentiated
for VUID classification.
* BuildModule: optionally avoid adding new OpLine instructions
Fixes#4029 for my use case
* Fix formatting
* Create last_line_inst_ only if doing extra line tracking
Fix buffer oob instrumentation for matrix refs.
Matrix stride decoration is not on matrix type but is a member decoration
on the enclosing struct type. Also correctly apply matrix stride depending
on row or column major.
spirv-opt has a bug that `DebugInfoManager::AddDebugValueWithIndex()` does not
preserve `Indexes` operands of
[DebugValue](https://www.khronos.org/registry/spir-v/specs/unified1/OpenCL.DebugInfo.100.html#DebugValue).
It has to preserve all of those `Indexes` operands, but it preserves only the first index
operand.
This PR removes `DebugInfoManager::AddDebugValueWithIndex()` and lets the spirv-opt
use `DebugInfoManager::AddDebugValueForDecl()`.
`DebugInfoManager::AddDebugValueForDecl()` preserves the Indexes operand correctly.
The front-end language compiler would simply emit DebugDeclare for
a variable when it is declared, which is effective through the variable's
scope. Since DebugDeclare only maps an OpVariable to a local variable,
the information can be removed when an optimization pass uses the
loaded value of the variable. DebugValue can be used to specify the
value of a variable. For each value update or phi instruction of a variable,
we can add DebugValue to help debugger inspect the variable at any
point of the program execution.
For example,
float a = 3;
... (complicated cfg) ...
foo(a); // <-- variable inspection: debugger can find DebugValue of `float a` in the nearest dominant
For the code with complicated CFG e.g., for-loop, if-statement, we
need help of ssa-rewrite to analyze the effective value of each variable
in each basic block.
If the value update of the variable happens only once and it dominates
all its uses, local-single-store-elim pass conducts the same value update
with ssa-rewrite and we have to let it add DebugValue for the value assignment.
One main issue is that we have to add DebugValue only when the value
update of a variable is visible to DebugDeclare. For example,
```
{ // scope1
%stack = OpVariable %ptr_int %int_3
{ // scope2
DebugDeclare %foo %stack <-- local variable "foo" in high-level language source code is declared as OpVariable "%stack"
// add DebugValue "foo = 3"
...
Store %stack %int_7 <-- foo = 7, add DebugValue "foo = 7"
...
// debugger can inspect the value of "foo"
}
Store %stack %int_11 <-- out of "scope2" i.e., scope of "foo". DO NOT add DebugValue "foo = 11"
}
```
However, the initalization of a variable is an exception.
For example, an argument passing of an inlined function must be done out of
the function's scope, but we must add a DebugValue for it.
```
// in HLSL
bar(float arg) { ... }
...
float foo = 3;
bar(foo);
// in SPIR-V
%arg = OpVariable
OpStore %arg %foo <-- Argument passing. Out of "float arg" scope, but we must add DebugValue for "float arg"
... body of function bar(float arg) ...
```
This PR handles the except case in local-single-store-elim pass. It adds
DebugValue for a store that is considered as an initialization.
The same exception handling code for ssa-rewrite is done by this commit: df4198e50e.
This fixes https://github.com/KhronosGroup/SPIRV-Tools/issues/3873.
In the presence of variable pointers, the reaching definition may be
another pointer. For example, the following fragment:
%2 = OpVariable %_ptr_Input_float Input
%11 = OpVariable %_ptr_Function__ptr_Input_float Function
OpStore %11 %2
%12 = OpLoad %_ptr_Input_float %11
%13 = OpLoad %float %12
corresponds to the pseudo-code:
layout(location = 0) in flat float *%2
float %13;
float *%12;
float **%11;
*%11 = %2;
%12 = *%11;
%13 = *%12;
which ultimately, should correspond to:
%13 = *%2;
During rewriting, the pointer %12 is found to be replaceable by %2.
However, when processing the load %13 = *%12, the type of %12's reaching
definition is another float pointer (%2), instead of a float value.
When this happens, we need to continue looking up the reaching definition
chain until we get to a float value or a non-target var (i.e. a variable
that cannot be SSA replaced, like %2 in this case since it is a function
argument).
This commit add support for optimizer to not inline functions with DontInline control flag, so that the [noinline] attribute in HLSL will be useful in DXC SPIR-V generation.
This is part of work of github.com/microsoft/DirectXShaderCompiler/issues/3158
Based on the OpLine spec, an OpLine instruction must be applied to
the instructions physically following it up to the first occurrence
of the next end of block, the next OpLine instruction, or the next
OpNoLine instruction.
```
OpLine %file 0 0
OpNoLine
OpLine %file 1 1
OpStore %foo %int_1
%value = OpLoad %int %foo
OpLine %file 2 2
```
For the above code, the current spirv-opt keeps three line
instructions `OpLine %file 0 0`, `OpNoLine`, and `OpLine %file 1 1`
in `std::vector<Instruction> dbg_line_insts_` of Instruction class
for `OpStore %foo %int_1`. It does not put any line instruction to
`std::vector<Instruction> dbg_line_insts_` of
`%value = OpLoad %int %foo` even though `OpLine %file 1 1` must be
applied to `%value = OpLoad %int %foo` based on the spec.
This results in the missing line information for
`%value = OpLoad %int %foo` while each spirv-opt pass optimizes the
code. We have to put `OpLine %file 1 1` to
`std::vector<Instruction> dbg_line_insts_` of
both `%value = OpLoad %int %foo` and `OpStore %foo %int_1`.
This commit conducts the line instruction propagation and skips
emitting the eliminated line instructions at the end, which are the same
with PropagateLineInfoPass and RedundantLineInfoElimPass. This
commit removes PropagateLineInfoPass and RedundantLineInfoElimPass.
KhronosGroup/glslang#2440 is a related PR that stop using
PropagateLineInfoPass and RedundantLineInfoElimPass from glslang.
When the code in this PR applied, the glslang tests will pass.
For some cases, we have DebugDecl invisible to a value assignment, but
the value assignment information is important i.e., debugger cannot inspect
the variable without the information. For example, a parameter of an inlined
function must have its value assignment i.e., argument passing out of its
function scope. If we simply remove DebugDecl because it is invisible to the
argument passing, we cannot inspec the variable.
This PR
- Adds DebugValue for DebugDecl invisible to a value assignment. We use
the value of the variable in the basic block that contains DebugDecl, which is
found by ssa-rewrite. If the value instruction does not dominate DebugDecl,
we use the value of the variable in the immediate dominator of the basic block.
- Checks the visibility of DebugDecl for Phi value assignment based on the
all value operands of the Phi. Since Phi just references multiple values from
multiple basic blocks, scopes of value operands must be regarded as the scope
of the Phi.
`DebugInfoManager::AddDebugValueIfVarDeclIsVisible()` adds
OpenCL.DebugInfo.100 DebugValue from DebugDeclare only when the
DebugDeclare is visible to the give scope. It helps us correctly
handle a reference variable e.g.,
{ // scope #1.
int foo = /* init */;
{ // scope #2.
int& bar = foo;
...
in the above code, we must not propagate DebugValue of `int& bar` for
store instructions in the scope #1 because it is alive only in
the scope #2.
We have an exception: If the given DebugDeclare is used for a function
parameter, `DebugInfoManager::AddDebugValueIfVarDeclIsVisible()` has
to always add DebugValue instruction regardless
of the scope. It is because the initializer (store instruction) for
the function parameter can be out of the function parameter's scope
(the function) in particular when the function was inlined.
Without this change, the function parameter value information always
disappears whenever we run the function inlining pass and
`DebugInfoManager::AddDebugValueIfVarDeclIsVisible()`.
1. DebugValue/DebugDeclare references of load/store must not change
the behaviors of the convert-local-access-chains pass
2. We have to properly set the scope and line information of new
instructions made by the convert-local-access-chains pass
In #3636, I missed that the instruction folder may create more than a
single constant per call. Since CCP was only checking whether one
constant had been created after folding, it was wrongly thinking that
the IR had not changed.
Fixes#3738.
This PR adds the NestingDepth function to StructuredCFGAnalysis.
This function, given a block id, returns the number of merge
constructs containing it.
This is needed by spirv-fuzz, but it makes sense to add it to
StructuredCFGAnalaysis, which contains related functionalities.
When we update OpenCL.DebugInfo.100 lexical scopes e.g., DebugFunction,
we have to replace DebugScope of each instruction that uses the lexical
scope correctly.
It is possible that the result of a void function call is used. In case
it is used, we need something that still defines its id after inlining.
We use an undef for that purpose.
Fixes https://github.com/KhronosGroup/SPIRV-Tools/issues/3704
CCP should mark IR changed if it created new constants.
This fixes#3636.
When CCP is simulating statements, it will sometimes successfully fold
an instruction, which laters switches to varying. The initial fold of
the instruction may generate a new constant K.
The problem we were running into is when K never gets propagated to the
IR. Its definition will still exist, so CCP should mark the IR modified
in this case.
In fixing this bug, I noticed that an existing test was suffering from
the same bug. The change also makes PassTest::SinglePassRunAndMatch()
return the result from the pass, so that we can check that the pass
marks the IR modified in this case.
In the existing code, ADCE pass does not check DebugScope of an
instruction when it checks the users of each instruction, which results
in removing OpenCL.Debug.100 instructions that are only used by
DebugScope. This commit lets ADCE pass add DebugScope of an instruction
to the live instruction set when the instruction is added to the live
instruction set.
* No longer blindly add global non-semantic info instructions to global
types and values
* functions now have a list of non-semantic instructions that succeed
them in the global scope
* global non-semantic instructions go in global types and values if
they appear before any function, otherwise they are attached to the
immediate function predecessor in the module
* changed ADCE to use the function removal utility
* Modified EliminateFunction to have special handling for non-semantic
instructions in the global scope
* non-semantic instructions are moved to an earlier function (or full
global set) if the function they are attached to is eliminated
* Added IRContext::KillNonSemanticInfo to remove the tree of
non-semantic instructions that use an instruction
* this is used in function elimination
* There is still significant work in the optimizer to handle
non-semantic instructions fully in the optimizer