The PPC MFCR instruction implicitly uses all 8 of the CR
registers. Currently it is not so marked, which leads to
VCMPEQ instructions that feed into it getting deleted.
If it is so marked, local RA complains about this sequence:
vreg = MCRF CR0
MFCR <kill of whatever preg got assigned to vreg>
All current uses of this instruction are only interested in
one of the 8 CR registers, so redefine MFCR to be a normal
unary instruction with a CR input (which is emitted only as
a comment). That avoids all problems. 7739628.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104238 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PowerPC/PPCISelLowering.h b/lib/Target/PowerPC/PPCISelLowering.h
index 1d05f3d..6dcaf1e 100644
--- a/lib/Target/PowerPC/PPCISelLowering.h
+++ b/lib/Target/PowerPC/PPCISelLowering.h
@@ -111,9 +111,10 @@
/// Return with a flag operand, matched by 'blr'
RET_FLAG,
- /// R32 = MFCR(CRREG, INFLAG) - Represents the MFCR/MFOCRF instructions.
- /// This copies the bits corresponding to the specified CRREG into the
- /// resultant GPR. Bits corresponding to other CR regs are undefined.
+ /// R32 = MFCR(CRREG, INFLAG) - Represents the MFCRpseud/MFOCRF
+ /// instructions. This copies the bits corresponding to the specified
+ /// CRREG into the resultant GPR. Bits corresponding to other CR regs
+ /// are undefined.
MFCR,
/// RESVEC = VCMP(LHS, RHS, OPC) - Represents one of the altivec VCMP*