[PATCH] D139874: [AMDGPU] Lower VGPR to physical SGPR COPY to S_MOV_B32 if VGPR contains the compile time constant

[Jon Chesterfield via Phabricator via llvm-commits]

JonChesterfield added inline comments.


================
Comment at: llvm/lib/Target/AMDGPU/SIFixSGPRCopies.cpp:856
+          if (IMMVal <= UINT32_MAX) {
+            Register TmpReg =
+                MRI->createVirtualRegister(&AMDGPU::SReg_32_XM0RegClass);
----------------
Not sure the signed comparison works here. INT64_MIN is smaller than UINT32_MAX. Checked getImm() and it does return a signed value, so I guess we either convert to unsigned then compare, or truncate to int32_t and check that is equal to the original


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D139874/new/

https://reviews.llvm.org/D139874