[llvm] [AMDGPU] Support function attribute to override postRA scheduling direction (PR #147708)

[Harrison Hao via llvm-commits]

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@@ -0,0 +1,34 @@
+; REQUIRES: asserts
+
+; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx1100 -debug-only=gcn-subtarget < %s 2>&1 | FileCheck %s
+; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx1100 < %s 2>&1 | FileCheck -check-prefixes=WARNING %s
+
+; CHECK: Post-MI-sched direction (postra-sched-topdown): topdown
+define float @postra-sched-topdown(float %input) nounwind #0 {
+  %x = fadd float %input, 1.000000e+00
+  ret float %x
+}
+
+; CHECK: Post-MI-sched direction (postra-sched-bottomup): bottomup
+define float @postra-sched-bottomup(float %input) nounwind #1 {
+  %x = fsub float %input, 1.000000e+00
+  ret float %x
+}
+
+; CHECK: Post-MI-sched direction (postra-sched-bidirectional): bidirectional
+define float @postra-sched-bidirectional(float %input) nounwind #2 {
+  %x = fadd float %input, 1.000000e+00
+  ret float %x
+}
+
+; CHECK: Post-MI-sched direction (postra-sched-warning): topdown
+; WARNING: invalid value for postRa direction attribute
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harrisonGPU wrote:

I have removed actual value of the attribute. :-)

https://github.com/llvm/llvm-project/pull/147708