diff options
| -rw-r--r-- | llvm/lib/Target/X86/X86Instr64bit.td | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/llvm/lib/Target/X86/X86Instr64bit.td b/llvm/lib/Target/X86/X86Instr64bit.td index c37a93377ed..10e66e88bee 100644 --- a/llvm/lib/Target/X86/X86Instr64bit.td +++ b/llvm/lib/Target/X86/X86Instr64bit.td @@ -255,6 +255,10 @@ def MOV64mi32 : RIi32<0xC7, MRM0m, (outs), (ins i64mem:$dst, i64i32imm:$src), // Sign/Zero extenders +// MOVSX64rr8 always has a REX prefix and it has an 8-bit register +// operand, which makes it a rare instruction with an 8-bit register +// operand that can never access an h register. If support for h registers +// were generalized, this would require a special register class. def MOVSX64rr8 : RI<0xBE, MRMSrcReg, (outs GR64:$dst), (ins GR8 :$src), "movs{bq|x}\t{$src, $dst|$dst, $src}", [(set GR64:$dst, (sext GR8:$src))]>, TB; |
