[PATCH] D46799: [x86][eflags] Fix PR37431 by teaching the EFLAGS copy lowering to specifically handle SETB_C* pseudo instructions.

[Craig Topper via Phabricator via llvm-commits]

craig.topper added inline comments.


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Comment at: llvm/test/CodeGen/X86/flags-copy-lowering.mir:526
+  ; CHECK-NOT:     $eflags =
+  ; CHECK:         %[[CF_EXT:[^:]*]]:gr16 = SUBREG_TO_REG 0, %[[CF_REG]], %subreg.sub_8bit
+  ; CHECK-NEXT:    %[[ZERO:[^:]*]]:gr32 = MOV32r0 implicit-def $eflags
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This looks wrong. You didn't do anything to put zeros in bits 15:8. SUBREG_TO_REG doesn't make that happen.


Repository:
  rL LLVM

https://reviews.llvm.org/D46799