Implements the following simplifications:
(a - b) + b => a
(a * b) + (a * c) => a * (b + c)
Also adds logic to simplification to handle rules that create new operations
that might need simplification, such as the second rule above.
Only perform the second simplification if the multiplies have the add as their
only use. Otherwise this is a deoptimization of size and performance.
* Ensure same enum values have consistent extension lists
* val: fix checking of capabilities
The operand for an OpCapability should only be
checked for the extension or core version.
The InstructionPass registers a capability, and all its implied
sub-capabilities before actually checking the operand to an
OpCapability.
* Add basic support for SPIR-V 1.5
- Adds SPV_ENV_UNIVERSAL_1_5
- Command line tools default to spv1.5 environment
- SPIR-V 1.5 incorporates several extensions. Now the disassembler
prefers outputing the non-EXT or non-KHR names. This requires
updates to many tests, to make strings match again.
- Command line tests: Expect SPIR-V 1.5 by default
* Test validation of SPIR-V 1.5 incorporated extensions
Starting with 1.5, incorporated features no longer require
the associated OpExtension instruction.
Fixes#2764
* Don't replace all uses when simplifying instructions, instead only
update non-debug, non-decoration uses
* added a test
* Add a new version of RAUW that takes a predicate to decide whether to
replace the use or not
* used in simplification pass
There are a couple spots where we are not looking at decorations when we should.
1. Value numbering is suppose to assign a different value number to ids if they have different decorations. However that is not being done for OpCopyObject and OpPhi.
1. Instruction simplification is propagating OpCopyObject instruction without checking for decorations. It should only do that if no decorations are being lost.
Add a new function to the decoration manager to check if the decorations of one id are a subset of the decorations of another.
Fixes#2715.
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.
