[llvm] [SPIRV] Add FPVariant tracking for floating-point registers in SPIR-V (PR #156871)

[Dmitry Sidorov via llvm-commits]

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@@ -2088,3 +2100,17 @@ bool SPIRVGlobalRegistry::hasBlockDecoration(SPIRVType *Type) const {
   }
   return false;
 }
+
+SPIRVGlobalRegistry::FPVariant
+SPIRVGlobalRegistry::getFPVariantForVReg(Register VReg,
+                                         const MachineFunction *MF) {
+  const MachineFunction *Func = MF ? MF : CurMF;
+  auto FuncIt = VRegFPVariantMap.find(Func);
+  if (FuncIt != VRegFPVariantMap.end()) {
+    const DenseMap<Register, FPVariant> &VRegMap = FuncIt->second;
+    auto VRegIt = VRegMap.find(VReg);
+    if (VRegIt != VRegMap.end())
+      return VRegIt->second;
+  }
+  return FPVariant::NONE;
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MrSidims wrote:

should we make it unreachable instead?

https://github.com/llvm/llvm-project/pull/156871