[PATCH] D98515: [AMDGPU][GlobalISel] Stop foldInsertEltToCmpSelect from changing reg banks

[Matt Arsenault via Phabricator via llvm-commits]

arsenm requested changes to this revision.
arsenm added inline comments.
This revision now requires changes to proceed.


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Comment at: llvm/lib/Target/AMDGPU/AMDGPURegisterBankInfo.cpp:2002
+    Register InReg = MI.getOperand(2).getReg();
+    if (DstBank == AMDGPU::VGPRRegBank && InsBank == AMDGPU::SGPRRegBank)
+      InReg = B.buildCopy(MRI.getType(InReg), InReg).getReg(0);
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OK I see what's happening now. I think this should introduce a new utility function to try to constrain a register to a register bank, or insert a copy if not (similar to the existing ones for concrete register classes). This should also be called below in place of the setRegBank where this is overwritten


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https://reviews.llvm.org/D98515