[llvm] [AMDGPU] Improve MemorySSA walking in isClobberedInFunction (PR #211817)

[Jay Foad via llvm-commits]

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@@ -32,7 +32,7 @@ define amdgpu_kernel void @add_reg_reg(ptr addrspace(1) %ptr) {
   ; CHECK-NEXT:   [[S_LOAD_DWORDX2_IMM:%[0-9]+]]:sreg_64_xexec_xnull = S_LOAD_DWORDX2_IMM [[COPY]](p4), 36, 0 :: (dereferenceable invariant load (s64) from %ir.ptr.kernarg.offset, align 4, addrspace 4)
   ; CHECK-NEXT:   [[V_MOV_B32_e32_:%[0-9]+]]:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
   ; CHECK-NEXT:   [[GLOBAL_LOAD_DWORDX2_SADDR:%[0-9]+]]:vreg_64 = GLOBAL_LOAD_DWORDX2_SADDR [[S_LOAD_DWORDX2_IMM]], [[V_MOV_B32_e32_]], 0, 0, implicit $exec :: (volatile "amdgpu-noclobber" load (s64) from %ir.ptr.load, addrspace 1)
-  ; CHECK-NEXT:   [[GLOBAL_LOAD_DWORDX2_SADDR1:%[0-9]+]]:vreg_64 = GLOBAL_LOAD_DWORDX2_SADDR [[S_LOAD_DWORDX2_IMM]], [[V_MOV_B32_e32_]], 0, 0, implicit $exec :: (volatile load (s64) from %ir.ptr.load, addrspace 1)
+  ; CHECK-NEXT:   [[GLOBAL_LOAD_DWORDX2_SADDR1:%[0-9]+]]:vreg_64 = GLOBAL_LOAD_DWORDX2_SADDR [[S_LOAD_DWORDX2_IMM]], [[V_MOV_B32_e32_]], 0, 0, implicit $exec :: (volatile "amdgpu-noclobber" load (s64) from %ir.ptr.load, addrspace 1)
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jayfoad wrote:

Related questions: https://discourse.llvm.org/t/memoryssawalker-getclobberingmemoryaccess-not-idempotent/91405

https://github.com/llvm/llvm-project/pull/211817