We are seeing shaders that have multiple returns in a functions. These
functions must get inlined for legalization purposes; however, the
inliner does not know how to inline functions that have multiple
returns.
The solution we will go with it to improve the merge return pass to
handle structured control flow.
Note that the merge return pass will assume the cfg has been cleanedup
by dead branch elimination.
Fixes#857.
Previously we keep a separate static grammar table for opcodes/
operands per SPIR-V version. This commit changes that to use a
single unified static grammar table for opcodes/operands.
This essentially changes how grammar facts are queried against
a certain target environment. There are only limited filtering
according to the desired target environment; a symbol is
considered as available as long as:
1. The target environment satisfies the minimal requirement of
the symbol; or
2. There is at least one extension enabling this symbol.
Note that the second rule assumes the extension enabling the
symbol is indeed requested in the SPIR-V code; checking that
should be the validator's work.
Also fixed a few grammar related issues:
* Rounding mode capability requirements are moved to client APIs.
* Reserved symbols not available in any extension is no longer
recognized by assembler.
Strips reflection info. This is limited to decorations and
decoration instructions related to the SPV_GOOGLE_hlsl_functionality1
extension.
It will remove the OpExtension for SPV_GOOGLE_hlsl_functionality1.
It will also remove the OpExtension for SPV_GOOGLE_decorate_string
if there are no further remaining uses of OpDecorateStringGOOGLE.
Fixes https://github.com/KhronosGroup/SPIRV-Tools/issues/1398
This reimplementation fixes several issues when removing decorations associated
to an ID (partially addresses #1174 and gives tools for fixing #898), as well
as making it easier to remove groups; a few additional tests have been added.
DecorationManager::RemoveDecoration() will still not delete dead decorations it
created, but I do not think it is its job either; given the following input
```
OpCapability Shader
OpCapability Linkage
OpMemoryModel Logical GLSL450
OpDecorate %2 Restrict
%2 = OpDecorationGroup
OpGroupDecorate %2 %1 %3
OpDecorate %4 Invariant
%4 = OpDecorationGroup
OpGroupDecorate %4 %2
%uint = OpTypeInt 32 0
%1 = OpVariable %uint Uniform
%3 = OpVariable %uint Uniform
```
which of the following two outputs would you expect RemoveDecoration(2) to produce:
```
OpCapability Shader
OpCapability Linkage
OpMemoryModel Logical GLSL450
%uint = OpTypeInt 32 0
%1 = OpVariable %uint Uniform
%3 = OpVariable %uint Uniform
```
or
```
OpCapability Shader
OpCapability Linkage
OpMemoryModel Logical GLSL450
OpDecorate %4 Invariant
%4 = OpDecorationGroup
%uint = OpTypeInt 32 0
%1 = OpVariable %uint Uniform
%3 = OpVariable %uint Uniform
```
Fixes https://github.com/KhronosGroup/SPIRV-Tools/issues/924
Fixes https://github.com/KhronosGroup/SPIRV-Tools/issues/1174
The default target is SPIR-V 1.3.
For example, spirv-as will generate a SPIR-V 1.3 binary by default.
Use command line option "--target-env spv1.0" if you want to make a SPIR-V
1.0 binary or validate against SPIR-V 1.0 rules.
Example:
# Generate a SPIR-V 1.0 binary instead of SPIR-V 1.3
spirv-as --target-env spv1.0 a.spvasm -o a.spv
spirv-as --target-env vulkan1.0 a.spvasm -o a.spv
# Validate as SPIR-V 1.0.
spirv-val --target-env spv1.0 a.spv
# Validate as Vulkan 1.0
spirv-val --target-env vulkan1.0 a.spv
The merging types we do not remove other information related to the
types. We simply leave it duplicated, and hope it is removed later.
This is what happens with decorations. They are removed in the next
phase of remove duplicates. However, for OpNames that is not the case.
We end up with two different names for the same id, which does not make
sense.
The solution is to remove the names and decorations for the type being
removed instead of rewriting them to refer to the other type.
Note that it is possible that if the first type does not have a name,
then the types will end up with no name. That is fine because the names
should not have any semantic significance anyway.
The was identified in issue #1372, but this does not fix that issue.
* Also mark function parameters as varying
* Conservatively mark assignment instructions as varying if any input is
varying after attempting to fold
* Added a test to catch this case
As per Vulkan spec, BuiltIn variables can't have Location or Component
decorations. On some drivers, these can lead to driver crashing when
compiling the shader pipeline; for example, NVidia/AMD desktop drivers:
https://github.com/KhronosGroup/glslang/issues/1182.
This change adds validation and tests to catch this.
* getFloatConstantKind() now handles OpConstantNull
* PerformOperation() now handles OpConstantNull for vectors
* Fixed some instances where we would attempt to merge a division by 0
* added tests
The algorithm used in DCEInst to remove dead code is very slow. It is
fine if you only want to remove a small number of instructions, but, if
you need to remove a large number of instructions, then the algorithm in
ADCE is much faster.
This PR removes the calls to DCEInst in the load-store removal passes
and adds a pass of ADCE afterwards.
A number of different iterations of the order of optimization, and I
believe this is the best I could find.
The results I have on 3 sets of shaders are:
Legalization:
Set 1: 5.39 -> 5.01
Set 2: 13.98 -> 8.38
Set 3: 98.00 -> 96.26
Performance passes:
Set 1: 6.90 -> 5.23
Set 2: 10.11 -> 6.62
Set 3: 253.69 -> 253.74
Size reduction passes:
Set 1: 7.16 -> 7.25
Set 2: 17.17 -> 16.81
Set 3: 112.06 -> 107.71
Note that the third set's compile time is large because of the large
number of basic blocks, not so much because of the number of
instructions. That is why we don't see much gain there.
Adding basis of arithmetic merging
* Refactored constant collection in ConstantManager
* New rules:
* consecutive negates
* negate of arithmetic op with a constant
* consecutive muls
* reciprocal of div
* Removed IRContext::CanFoldFloatingPoint
* replaced by Instruction::IsFloatingPointFoldingAllowed
* Fixed some bad tests
* added some header comments
Added PerformIntegerOperation
* minor fixes to constants and tests
* fixed IntMultiplyBy1 to work with 64 bit ints
* added tests for integer mul merging
Adding test for vector integer multiply merging
Adding support for merging integer add and sub through negate
* Added tests
Adding rules to merge mult with preceding divide
* Has a couple tests, but needs more
* Added more comments
Fixed bug in integer division folding
* Will no longer merge through integer division if there would be a
remainder in the division
* Added a bunch more tests
Adding rules to merge divide and multiply through divide
* Improved comments
* Added tests
Adding rules to handle mul or div of a negation
* Added tests
Changes for review
* Early exit if no constants are involved in more functions
* fixed some comments
* removed unused declaration
* clarified some logic
Adding new rules for add and subtract
* Fold adds of adds, subtracts or negates
* Fold subtracts of adds, subtracts or negates
* Added tests
This change makes the IR builder use the type manager to generate
OpTypeInts when creating OpConstants. This avoids dangling references
being stored by the created OpConstants.
It moves all conditional branching and switch whose conditions are loop
invariant and uniform. Before performing the loop unswitch we check that
the loop does not contain any instruction that would prevent it
(barriers, group instructions etc.).
Fixes a bug at the same time. In `UpdateDefUse`, if the definition
already exists, we are not suppose to analyse it again. When you do
the entries for the definition are deleted, and we don't want that.
The check for this was wrong.
This function now checks for side-effects before adding operand
instructions to the dead instruction work list.
Because this fix puts more pressure on IsCombinatorInstruction() to
be correct, this commit adds all OpConstant* and OpType* instructions
to combinator_ops_ set.
Fixes#1341.
This change implements instruction folding for arithmetic operations
that are redundant, specifically:
x + 0 = 0 + x = x
x - 0 = x
0 - x = -x
x * 0 = 0 * x = 0
x * 1 = 1 * x = x
0 / x = 0
x / 1 = x
mix(a, b, 0) = a
mix(a, b, 1) = b
Cache ExtInst import id in feature manager
This allows us to avoid string lookups during optimization; for now we
just cache GLSL std450 import id but I can imagine caching more sets as
they become utilized by the optimizer.
Add tests for add/sub/mul/div/mix folding
The tests cover scalar float/double cases, and some vector cases.
Since most of the code for floating point folding is shared, the tests
for vector folding are not as exhaustive as scalar.
To test sub->negate folding I had to implement a custom fixture.
I mixed up two cases when folding an OpCompositeExtract that is feed by
and OpCompositeInsert. The specific cases are demonstracted in the new
test. I mixed up the conditions for the cases, and treated one like the
other.
Fixes#1323.
* Now track propagation status and assert on bad statuses
* Added helper methods to access instruction propagation status
* Modified the phi meet operator to properly reflect the paper it is
based on
* Modified SSA edge addition so that all edge are added, but only on
state changes
* Fixed a bug in instruction simulation where interesting conditional
branches would not mark the interesting edge as executed
* Added a test to catch this bug
* Added an ostream operator for SSAPropagator::PropStatus
This change handles all 6 regular comparison types in two variations,
ordered (true if values are ordered *and* comparison is true) and
unordered (true if values are unordered *or* comparison is true).
Ordered comparison matches the default floating-point behavior on host
but we use std::isnan to check ordering explicitly anyway.
This change also slightly reworks the floating-point folding support
code to make it possible to define a folding operation that returns
boolean instead of floating point.
These tests exhaustively test ordered/unordered comparisons for
float/double.
Since for NaN inputs the comparison result doesn't depend on the
comparison function, we just test == and !=; NaN inputs result in true
unordered comparisons and false ordered comparisons.
In dead branch elimination, we already recognize unreachable continue
blocks, and update OpPhi instruction accordingly. This change adds an
extra check: if the head block has exactly 1 other incoming edge, then
replace the OpPhi with the value from that edge.
Fixes#1314.
unordered_map is not POD. Using it as static may cause problems
when operator new() and operator delete() is customized.
Also changed some function signatures to use const char* instead
of std::string, which will give caller the flexibility to avoid
creating a std::string.
We can fold OpSelect into one of the operands in two cases:
- condition is constant
- both results are the same
Even if the original shader doesn't have either of these, if-conversion
pass sometimes ends up generating instructions like
%7127 = OpSelect %int %3220 %7058 %7058
And this optimization cleans them up.
This patch adds initial support for loop unrolling in the form of a
series of utility classes which perform the unrolling. The pass can
be run with the command spirv-opt --loop-unroll. This will unroll
loops within the module which have the unroll hint set. The unroller
imposes a number of requirements on the loops it can unroll. These are
documented in the comments for the LoopUtils::CanPerformUnroll method in
loop_utils.h. Some of the restrictions will be lifted in future patches.
Implementation of the simplification pass.
- Create pass that calls the instruction folder on each instruction and
propagate instructions that fold to a copy. This will do copy
propagation as well.
- Did not use the propagator engine because I want to modify the instruction
as we go along.
- Change folding to not allocate new instructions, but make changes in
place. This change had a big impact on compile time.
- Add simplification pass to the legalization passes in place of
insert-extract elimination.
- Added test cases for new folding rules.
- Added tests for the simplification pass
- Added a method to the CFG to apply a function to the basic blocks in
reverse post order.
Contributes to #1164.
Add pkg-config file for shared libraries
Properly build SPIRV-Tools DLL
Test C interface with shared library
Set PATH to shared library file for c_interface_shared test
Otherwise, the test won't find SPIRV-Tools-shared.dll.
Do not use private functions when testing with shared library
Make all symbols hidden by default for shared library target
