[llvm] [LiveVariables] Mark use as implicit-def if defined at instr (PR #119446)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,28 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mtriple=amdgcn -mcpu=gfx900 -O1 %s -o - | FileCheck %s
+
+define amdgpu_ps <4 x float> @caller(ptr %1) {
+; CHECK-LABEL: caller:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    flat_load_dword v1, v[0:1]
+; CHECK-NEXT:    s_getpc_b64 s[0:1]
+; CHECK-NEXT:    s_add_u32 s0, s0, fn at gotpcrel32@lo+4
+; CHECK-NEXT:    s_addc_u32 s1, s1, fn at gotpcrel32@hi+12
+; CHECK-NEXT:    s_load_dwordx2 s[4:5], s[0:1], 0x0
+; CHECK-NEXT:    s_mov_b32 s0, 0
+; CHECK-NEXT:    s_mov_b32 s1, 0
+; CHECK-NEXT:    s_mov_b32 s2, 0
+; CHECK-NEXT:    s_mov_b64 s[8:9], 36
+; CHECK-NEXT:    v_mov_b32_e32 v0, 0
+; CHECK-NEXT:    s_mov_b32 s3, 0
+; CHECK-NEXT:    v_mov_b32_e32 v2, 0
+; CHECK-NEXT:    s_mov_b32 s32, 0
+; CHECK-NEXT:    s_waitcnt lgkmcnt(0)
+; CHECK-NEXT:    s_swappc_b64 s[30:31], s[4:5]
+; CHECK-NEXT:    ; return to shader part epilog
+  %L = load i32, ptr %1, align 4
+  %R = call <4 x float> @fn(<4 x i32> zeroinitializer, i32 0, i32 %L, i32 0)
+  ret <4 x float> %R
+}
+
+declare <4 x float> @fn(<4 x i32> inreg, i32, i32, i32)
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arsenm wrote:

Is the inreg significant here? Also "declare hidden" if it still reproduces with it 

https://github.com/llvm/llvm-project/pull/119446