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

[Farzon Lotfi via llvm-commits]

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@@ -2564,8 +2577,54 @@ Register SPIRVInstructionSelector::buildOnesVal(bool AllOnes,
 
 bool SPIRVInstructionSelector::selectSelect(Register ResVReg,
                                             const SPIRVType *ResType,
-                                            MachineInstr &I,
-                                            bool IsSigned) const {
+                                            MachineInstr &I) const {
+  bool IsFloatTy =
+      GR.isScalarOrVectorOfType(I.getOperand(2).getReg(), SPIRV::OpTypeFloat) ||
+      GR.isScalarOrVectorOfType(I.getOperand(3).getReg(), SPIRV::OpTypeFloat);
+
+  bool IsPtrTy =
+      GR.isScalarOrVectorOfType(I.getOperand(2).getReg(),
+                                SPIRV::OpTypePointer) ||
+      GR.isScalarOrVectorOfType(I.getOperand(3).getReg(), SPIRV::OpTypePointer);
+  bool IsVectorTy =
+      GR.getSPIRVTypeForVReg(I.getOperand(2).getReg())->getOpcode() ==
+          SPIRV::OpTypeVector ||
+      GR.getSPIRVTypeForVReg(I.getOperand(3).getReg())->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;
----------------
farzonl wrote:

I actually don't like how this one was designed because it went really hard on the tablegen unnecessarily. But essentially G_Select was not an instruction they wanted to legalize and instead it is handled as part of resolving `SPIRV::ASSIGN_TYPE`.

>From what I noticed There is a verifier step after instruction selection and they have typed versions of every opcode to help the verifier. But how the executeMatchTable/getMatchTable was done because of all these OpSelects meant that we were never toggling to use the right one for this case.

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