Commit Graph

8 Commits

Author SHA1 Message Date
Craig Topper 6934202dc0 [MachineLICM][X86][AMDGPU] Fix subtle bug in the updating of PhysRegClobbers in post-RA LICM
It looks like MCRegAliasIterator can visit the same physical register twice. When this happens in this code in LICM we end up setting the PhysRegDef and then later in the same loop visit the register again. Now we see that PhysRegDef is set from the earlier iteration so now set PhysRegClobber.

This patch splits the loop so we have one that uses the previous value of PhysRegDef to update PhysRegClobber and second loop that updates PhysRegDef.

The X86 atomic test is an improvement. I had to add sideeffect to the two shrink wrapping tests to prevent hoisting from occurring. I'm not sure about the AMDGPU tests. It looks like the branch instruction changed at end the of the loops. And in the branch-relaxation test I think there is now "and vcc, exec, -1" instruction that wasn't there before.

Differential Revision: https://reviews.llvm.org/D55102

llvm-svn: 348330
2018-12-05 03:41:26 +00:00
Stanislav Mekhanoshin e86c8d33b1 [AMDGPU] Optimize S_CBRANCH_VCC[N]Z -> S_CBRANCH_EXEC[N]Z
Sometimes after basic block placement we end up with a code like:

  sreg = s_mov_b64 -1
  vcc = s_and_b64 exec, sreg
  s_cbranch_vccz

This happens as a join of a block assigning -1 to a saved mask and
another block which consumes that saved mask with s_and_b64 and a
branch.

This is essentially a single s_cbranch_execz instruction when moved
into a single new basic block.

Differential Revision: https://reviews.llvm.org/D54164

llvm-svn: 346690
2018-11-12 18:48:17 +00:00
Stanislav Mekhanoshin 20d4795d93 [AMDGPU] Enable LICM in the BE pipeline
This allows to hoist code portion to compute reciprocal of loop
invariant denominator in integer division after codegen prepare
expansion.

Differential Revision: https://reviews.llvm.org/D48604

llvm-svn: 335988
2018-06-29 16:26:53 +00:00
Changpeng Fang 391bcf8893 AMDGPU/SI: Handle infinite loop for the structurizer to work with CFG with infinite loops.
Summary:
  The current StructurizeCFG pass only works for CFG with one exit. AMDGPUUnifyDivergentExitNodes combines multiple "return" blocks and/or "unreachable" blocks
to one exit block for the Structurizer to work. However, infinite loop is another kind of special "exit", and if we don't handle it, the case of multiple exits will prevent the structurizer from working.

In this work, for each infinite loop, we add a dummy edge to the "return" block, and thus the AMDGPUUnifyDivergentExitNodes pass will work with infinite loops.
This will make CFG with infinite loops be structurized.

Reviewer:
  nhaehnle

Differential Revision:
  https://reviews.llvm.org/D46340

llvm-svn: 332625
2018-05-17 16:45:01 +00:00
Mark Searles 70359ac60d [AMDGPU] Turn on the new waitcnt insertion pass. Adjust tests.
-enable-si-insert-waitcnts=1 becomes the default
-enable-si-insert-waitcnts=0 to use old pass

Differential Revision: https://reviews.llvm.org/D33730

llvm-svn: 304551
2017-06-02 14:19:25 +00:00
Matt Arsenault 3dbeefa978 AMDGPU: Mark all unspecified CC functions in tests as amdgpu_kernel
Currently the default C calling convention functions are treated
the same as compute kernels. Make this explicit so the default
calling convention can be changed to a non-kernel.

Converted with perl -pi -e 's/define void/define amdgpu_kernel void/'
on the relevant test directories (and undoing in one place that actually
wanted a non-kernel).

llvm-svn: 298444
2017-03-21 21:39:51 +00:00
Matt Arsenault 7aad8fd8f4 Enable FeatureFlatForGlobal on Volcanic Islands
This switches to the workaround that HSA defaults to
for the mesa path.

This should be applied to the 4.0 branch.

Patch by Vedran Miletić <vedran@miletic.net>

llvm-svn: 292982
2017-01-24 22:02:15 +00:00
Tom Stellard 45bb48ea19 R600 -> AMDGPU rename
llvm-svn: 239657
2015-06-13 03:28:10 +00:00