diff options
Diffstat (limited to 'llvm/lib/Target/X86/X86InstrCompiler.td')
| -rw-r--r-- | llvm/lib/Target/X86/X86InstrCompiler.td | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/llvm/lib/Target/X86/X86InstrCompiler.td b/llvm/lib/Target/X86/X86InstrCompiler.td index 71b43a38dc2..bc08147506c 100644 --- a/llvm/lib/Target/X86/X86InstrCompiler.td +++ b/llvm/lib/Target/X86/X86InstrCompiler.td @@ -1320,6 +1320,15 @@ def : Pat<(i64 (anyext GR16:$src)), def : Pat<(i64 (anyext GR32:$src)), (INSERT_SUBREG (i64 (IMPLICIT_DEF)), GR32:$src, sub_32bit)>; +// If this is an anyext of the remainder of an 8-bit sdivrem, use a MOVSX +// instead of a MOVZX. The sdivrem lowering will emit emit a MOVSX to move +// %ah to the lower byte of a register. By using a MOVSX here we allow a +// post-isel peephole to merge the two MOVSX instructions into one. +def anyext_sdiv : PatFrag<(ops node:$lhs), (anyext node:$lhs),[{ + return (N->getOperand(0).getOpcode() == ISD::SDIVREM && + N->getOperand(0).getResNo() == 1); +}]>; +def : Pat<(i32 (anyext_sdiv GR8:$src)), (MOVSX32rr8 GR8:$src)>; // Any instruction that defines a 32-bit result leaves the high half of the // register. Truncate can be lowered to EXTRACT_SUBREG. CopyFromReg may |
