[llvm] [SPIR-V] Fix sub-byte argument type mismatch in call lowering (PR #189893)

[Dmitry Sidorov via llvm-commits]

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@@ -395,7 +395,6 @@ bool SPIRVCallLowering::lowerFormalArguments(MachineIRBuilder &MIRBuilder,
     assert(VRegs[i].size() == 1 && "Formal arg has multiple vregs");
     Register ArgReg = VRegs[i][0];
     MRI->setRegClass(ArgReg, GR->getRegClass(ArgTypeVRegs[i]));
-    MRI->setType(ArgReg, GR->getRegType(ArgTypeVRegs[i]));
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MrSidims wrote:

So, the idea basically is: the SPIR-V type is tracked separately via assignSPIRVTypeToVReg, and the GMIR-level LLT should remain as the IRTranslator set it. The SPIRVPreLegalizer will later uniformly widen all sub-byte LLTs consistently across both defs and uses. Is it correct?

https://github.com/llvm/llvm-project/pull/189893