[llvm] [Verifier][AMDGPU] Restrict targets for chain calling convention. (PR #157469)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,6 @@
+; RUN: not llc -mtriple=amdgcn -mcpu=gfx1200 -o - < %s 2>&1 | FileCheck %s
+
+define amdgpu_cs_chain void @test_alloca() {
+; CHECK: Chain calling convention is invalid on this target
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arsenm wrote:

I reject the notion that IR can be invalid for an architecture 

https://github.com/llvm/llvm-project/pull/157469