[llvm] [AMDGPU] si-peephole-sdwa: Fix cndmask vcc use for wave32 (PR #139541)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,40 @@
+; RUN: llc %s -march=amdgcn -mcpu=gfx1030 -o - 2>&1 | FileCheck %s
+
+; In this test, V_CNDMASK_B32_e64 gets converted to V_CNDMASK_B32_e32,
+; but the expected conversion to SDWA does not occur.  This led to a
+; compilation error, because the use of $vcc in the resulting
+; instruction must be fixed to $vcc_lo for wave32 which only happened
+; after the full conversion to SDWA.
+
+
+; CHECK-NOT: {{.*}}V_CNDMASK_B32_e32{{.*}}$vcc
+; CHECK-NOT: {{.*}}Bad machine code: Virtual register defs don't dominate all uses
+; CHECK: {{.*}}v_cndmask_b32_e32{{.*}}vcc_lo
+
+define amdgpu_kernel void @quux(i32 %arg, i1 %arg1, i1 %arg2) {
+bb:
+  br i1 %arg1, label %bb9, label %bb3
+
+bb3:                                              ; preds = %bb
+  %call = tail call i32 @llvm.amdgcn.workitem.id.x()
+  %mul = mul i32 %call, 5
+  %zext = zext i32 %mul to i64
+  %getelementptr = getelementptr i8, ptr addrspace(1) null, i64 %zext
+  %getelementptr4 = getelementptr i8, ptr addrspace(1) %getelementptr, i64 4
+  %load = load i8, ptr addrspace(1) %getelementptr4, align 1
+  %getelementptr5 = getelementptr i8, ptr addrspace(1) %getelementptr, i64 3
+  %load6 = load i8, ptr addrspace(1) %getelementptr5, align 1
+  %insertelement = insertelement <5 x i8> poison, i8 %load, i64 4
+  %select = select i1 %arg2, <5 x i8> %insertelement, <5 x i8> <i8 poison, i8 poison, i8 poison, i8 poison, i8 0>
+  %insertelement7 = insertelement <5 x i8> %select, i8 %load6, i64 0
+  %icmp = icmp ult i32 0, %arg
+  %select8 = select i1 %icmp, <5 x i8> zeroinitializer, <5 x i8> %insertelement7
+  %shufflevector = shufflevector <5 x i8> zeroinitializer, <5 x i8> %select8, <5 x i32> <i32 0, i32 1, i32 7, i32 8, i32 9>
+  br label %bb9
+
+bb9:                                              ; preds = %bb3, %bb
+  %phi = phi <5 x i8> [ %shufflevector, %bb3 ], [ zeroinitializer, %bb ]
+  %extractelement = extractelement <5 x i8> %phi, i64 0
+  store i8 %extractelement, ptr addrspace(1) null, align 1
+  ret void
+}
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arsenm wrote:

```suggestion
}

```

Missing end of file newline 

https://github.com/llvm/llvm-project/pull/139541