[llvm] [SPIRV] Create a new OpSelect selector and fix register types. (PR #152311)

[Finn Plummer via llvm-commits]

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@@ -2565,8 +2578,52 @@ Register SPIRVInstructionSelector::buildOnesVal(bool AllOnes,
 
 bool SPIRVInstructionSelector::selectSelect(Register ResVReg,
                                             const SPIRVType *ResType,
-                                            MachineInstr &I,
-                                            bool IsSigned) const {
+                                            MachineInstr &I) const {
+  Register SelectFirstArg = I.getOperand(2).getReg();
+  Register SelectSecondArg = I.getOperand(3).getReg();
+  assert(ResType == GR.getSPIRVTypeForVReg(SelectFirstArg) &&
+         ResType == GR.getSPIRVTypeForVReg(SelectSecondArg));
+
+  bool IsFloatTy =
+      GR.isScalarOrVectorOfType(SelectFirstArg, SPIRV::OpTypeFloat);
+  bool IsPtrTy =
+      GR.isScalarOrVectorOfType(SelectFirstArg, SPIRV::OpTypePointer);
+  bool IsVectorTy = GR.getSPIRVTypeForVReg(SelectFirstArg)->getOpcode() ==
+                    SPIRV::OpTypeVector;
+
+  bool IsScalarBool =
+      GR.isScalarOfType(I.getOperand(1).getReg(), SPIRV::OpTypeBool);
+  unsigned Opcode;
+  if (IsVectorTy) {
+    if (IsFloatTy) {
+      Opcode = IsScalarBool ? SPIRV::OpSelectVFSCond : SPIRV::OpSelectVFVCond;
+    } else if (IsPtrTy) {
+      Opcode = IsScalarBool ? SPIRV::OpSelectVPSCond : SPIRV::OpSelectVPVCond;
+    } else {
+      Opcode = IsScalarBool ? SPIRV::OpSelectVISCond : SPIRV::OpSelectVIVCond;
+    }
+  } else {
+    if (IsFloatTy) {
+      Opcode = IsScalarBool ? SPIRV::OpSelectSFSCond : SPIRV::OpSelectVFVCond;
----------------
inbelic wrote:

IIUC, `IsScalarBool` detects if the condition is a scalar or vector.

Shouldn't we assert that `IsScalarBool` is true? `VFV` doesn't seem correct because the float operands would be a scalar in this case.

https://github.com/llvm/llvm-project/pull/152311