[llvm] [InstCombine] Add assume-based optimizations for equality and AMDGPU ballot patterns (PR #160670)

[Jay Foad via llvm-commits]

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@@ -3540,6 +3540,79 @@ Instruction *InstCombinerImpl::visitCallInst(CallInst &CI) {
       }
     }
 
+    // Basic assume equality optimization: assume(x == c) -> replace dominated uses of x with c
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jayfoad wrote:

Of course uses of x are dominated by the definition of x. This comment refers to uses of x dominated by the "assume".

https://github.com/llvm/llvm-project/pull/160670