[llvm] [AMDGPU] Account for existing SDWA selections (PR #123221)

[Matt Arsenault via llvm-commits]

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@@ -88,6 +88,42 @@ class SIPeepholeSDWALegacy : public MachineFunctionPass {
 
 using namespace AMDGPU::SDWA;
 
+/// Check that the SDWA selections \p Sel and \p OperandSel
+/// are suitable for being combined by combineSdwaSel.
+bool compatibleSelections(SdwaSel Sel, SdwaSel OperandSel) {
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arsenm wrote:

static 

https://github.com/llvm/llvm-project/pull/123221