[llvm] [AMDGPU] Optimize DPP for fmin/fmax functions (PR #195282)

[Joseph Huber via llvm-commits]

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@@ -489,6 +490,44 @@ static bool isIdentityValue(unsigned OrigMIOp, MachineOperand *OldOpnd) {
     if (OldOpnd->getImm() == 1)
       return true;
     break;
+  case AMDGPU::V_MIN_F32_e32:
+  case AMDGPU::V_MIN_F32_e64:
+    if (static_cast<uint32_t>(OldOpnd->getImm()) == /*+inf=*/0x7F800000)
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jhuber6 wrote:

I think the main limitation is f16, but we could just do `-inf` for those

https://github.com/llvm/llvm-project/pull/195282