[llvm] [AMDGPU] Add flag to enable expensive trip counts for runtime unroll. (PR #171735)

[via llvm-commits]

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@@ -0,0 +1,77 @@
+; RUN: opt -mtriple=amdgcn-amd-amdhsa -passes=loop-unroll -S %s -o - | FileCheck -check-prefixes=CHECK-NOUNROLL %s
+; RUN: opt -amdgpu-unroll-runtime-expensive-trip-count -mtriple=amdgcn-amd-amdhsa -passes=loop-unroll -S %s -o - | FileCheck -check-prefixes=CHECK-UNROLL %s
+
+
+; CHECK-LABEL: @_Z6kernelPilll(
+; CHECK: for.body:
+
+; CHECK-NOUNROLL: store
+; CHECK-NOUNROLL-NOT: store
+; CHECK-NOUNROLL: br
+
+; CHECK-UNROLL: store
+; CHECK-UNROLL: store
+; CHECK-UNROLL: store
+; CHECK-UNROLL: store
+; CHECK-UNROLL: store
+; CHECK-UNROLL: store
+; CHECK-UNROLL: store
+; CHECK-UNROLL: store
+; CHECK-UNROLL: br
+
+
+; Function Attrs: nofree norecurse nosync nounwind memory(argmem: write)
+define protected amdgpu_kernel void @_Z6kernelPilll(ptr addrspace(1) noundef writeonly captures(none) %a.coerce, i64 noundef %n, i64 noundef %k, i64 noundef %s) local_unnamed_addr #0 {
+entry:
+  %0 = tail call ptr addrspace(4) @llvm.amdgcn.implicitarg.ptr()
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carlobertolli wrote:

done

https://github.com/llvm/llvm-project/pull/171735