Debug[No]Line are tracked and optimized using the same mechanism that tracks
and optimizes Op[No]Line.
Also:
- Fix missing DebugScope at top of block.
- Allow scalar replacement of access chain in DebugDeclare
This change allows the reducer to merge together blocks even when they
are unreachable, but keeps the restriction of reachability in place
for the optimizer.
Fixes#4302.
There was a lot of code in the codebase that would get the dominator
analysis for a function and then use it to check whether a block is
reachable. In the fuzzer, a utility method had been introduced to make
this more concise, but it was not being used consistently.
This change moves the utility method to IRContext, so that it can be
used throughout the codebase, and refactors all existing checks for
block reachability to use the utility method.
As explained in #3118, spirv-opt merge-blocks pass causes a
spirv-val error when an OpBranch has an OpLine in front of it.
OpLoopMerge
OpBranch ; Will be killed by merge-blocks pass
OpLabel ; Will be killed by merge-blocks pass
OpLine ; will be placed between OpLoopMerge and OpBranch - error!
OpBranch
To fix this issue, this commit moves line info of OpBranch to
OpLoopMerge.
Fixes#3118
* Validate that if a construct contains a header and it's merge is
reachable, the construct also contains the merge
* updated block merging to not merge into the continue
* update inlining to mark the original block of a single block loop as
the continue
* updated some tests
* remove dead code
* rename kBlockTypeHeader to kBlockTypeSelection for clarity
* Fixes#2338. Added check for phi node before merging blocks.
* Added functionality to merge blocks A and B even when B starts with OpPhi instructions, by replacing uses of the OpPhi results with the definitions coming from A. Added some tests for this.
* Fixed assertion.
