Spirv-opt has not had to handle module with function declarations. This
lead many passes to assume that every function has a body. This is not
always true. This commit will modify a number of passes to handle
function declarations.
Fixes https://github.com/KhronosGroup/SPIRV-Tools/issues/4443
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.
Adds a scalar replacement pass. The pass considers all function scope
variables of composite type. If there are accesses to individual
elements (and it is legal) the pass replaces the variable with a
variable for each composite element and updates all the uses.
Added the pass to -O
Added NumUses and NumUsers to DefUseManager
Added some helper methods for the inst to block mapping in context
Added some helper methods for specific constant types
No longer generate duplicate pointer types.
* Now searches for an existing pointer of the appropriate type instead
of failing validation
* Fixed spec constant extracts
* Addressed changes for review
* Changed RunSinglePassAndMatch to be able to run validation
* current users do not enable it
Added handling of acceptable decorations.
* Decorations are also transfered where appropriate
Refactored extension checking into FeatureManager
* Context now owns a feature manager
* consciously NOT an analysis
* added some test
* fixed some minor issues related to decorates
* added some decorate related tests for scalar replacement
Adds a pass that looks for redundant instruction in a function, and
removes them. The algorithm is a hash table based value numbering
algorithm that traverses the dominator tree.
This pass removes completely redundant instructions, not partially
redundant ones.
