[llvm] [AMDGPU] Merge two V_CNDMASK instructions into V_DUAL_CNDMASK (PR #135007)

[Jay Foad via llvm-commits]

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@@ -105,6 +105,25 @@ class SIFoldOperandsImpl {
     }
   }
 
+  unsigned getInverseCompareOpcode(MachineInstr &MI) const {
+    switch (MI.getOpcode()) {
+    case AMDGPU::V_CMP_EQ_U32_e64:
+      return AMDGPU::V_CMP_NE_U32_e64;
+    case AMDGPU::V_CMP_NE_U32_e64:
+      return AMDGPU::V_CMP_EQ_U32_e64;
+    case AMDGPU::V_CMP_GE_U32_e64:
+      return AMDGPU::V_CMP_LT_U32_e64;
+    case AMDGPU::V_CMP_LE_U32_e64:
+      return AMDGPU::V_CMP_GT_U32_e64;
+    case AMDGPU::V_CMP_GT_U32_e64:
+      return AMDGPU::V_CMP_LE_U32_e64;
+    case AMDGPU::V_CMP_LT_U32_e64:
+      return AMDGPU::V_CMP_GE_U32_e64;
+    default:
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jayfoad wrote:

Should also handle floating point comparisons?

https://github.com/llvm/llvm-project/pull/135007