[llvm] [AMDGPU][SIPreEmitPeephole] pre-commit tests: mustRetainExeczBranch: use a cost model (PR #109816)

[Juan Manuel Martinez Caamaño via llvm-commits]

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+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mtriple=amdgcn -mcpu=gfx1010 < %s | FileCheck -check-prefixes=GFX10,GFX1010 %s
+; RUN: llc -mtriple=amdgcn -mcpu=gfx1030 < %s | FileCheck -check-prefixes=GFX10,GFX1030 %s
+
+define void @convergent_cmp_no_metadata(i32 noundef inreg %value, ptr addrspace(8) nocapture writeonly inreg %res, i32 noundef inreg %v_offset, i32 noundef inreg %0, i32 noundef inreg %flag) {
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jmmartinez wrote:

That's weird.

You're right, there is nothing convergent here (it would be different if it was a kernel and not a function)

Would the comparison `%cmp = icmp sgt i32 %flag, 0` generate some other kind of branch (other than `s_cbranch_scc1`) if it was not convergent ?

https://github.com/llvm/llvm-project/pull/109816