[llvm] [AMDGPU] Add verification for amdgcn.init.exec.from.input (PR #128172)

[Robert Imschweiler via llvm-commits]

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@@ -0,0 +1,27 @@
+; RUN: sed -e '/^; MARK$/,$d' %s | not llc -mtriple=amdgcn -mcpu=gfx942 2>&1 | FileCheck %s
+; RUN: sed -e '1,/^; MARK$/d' %s | llc -mtriple=amdgcn -mcpu=gfx942 -filetype=null
+
+; Function Attrs: convergent nocallback nofree nounwind willreturn
+declare void @llvm.amdgcn.init.exec.from.input(i32, i32 immarg) #0
+attributes #0 = { convergent nocallback nofree nounwind willreturn }
+
+; CHECK: only inreg arguments to the parent function are valid as inputs to this intrinsic
+; CHECK-NEXT: call void @llvm.amdgcn.init.exec.from.input(i32 0, i32 0)
+define amdgpu_ps void @init_exec_from_input_fail_immarg(i32 inreg %a, i32 %b) {
+  call void @llvm.amdgcn.init.exec.from.input(i32 0, i32 0)
+  ret void
+}
+
+; CHECK: only inreg arguments to the parent function are valid as inputs to this intrinsic
+; CHECK-NEXT: call void @llvm.amdgcn.init.exec.from.input(i32 %b, i32 0)
+define amdgpu_ps void @init_exec_from_input_fail_not_inreg(i32 inreg %a, i32 %b) {
+  call void @llvm.amdgcn.init.exec.from.input(i32 %b, i32 0)
+  ret void
+}
+
+; MARK
+
+define amdgpu_ps void @init_exec_from_input_success(i32 inreg %a, i32 %b) {
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ro-i wrote:

True, there already are tests in CodeGen/AMDGPU testing the valid cases

https://github.com/llvm/llvm-project/pull/128172