diff options
| author | Chris Lattner <sabre@nondot.org> | 2010-11-06 22:35:34 +0000 |
|---|---|---|
| committer | Chris Lattner <sabre@nondot.org> | 2010-11-06 22:35:34 +0000 |
| commit | 04a75abe234f1093f69a065d799b3271ccd09f99 (patch) | |
| tree | e77b731d944364840e6419af7ed18895d42038a7 | |
| parent | d5b2f1aa8ce09624b0d0fd133e6cf0829dea57c8 (diff) | |
add aliases for movs between seg registers and mem. There are multiple
different forms of this instruction (movw/movl/movq) which we reported
as being ambiguous. Since they all do the same thing, gas just picks the
one with the shortest encoding. Follow its lead here.
This implements rdar://8208615
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118362 91177308-0d34-0410-b5e6-96231b3b80d8
| -rw-r--r-- | lib/Target/X86/X86InstrInfo.td | 5 | ||||
| -rw-r--r-- | test/MC/X86/x86-64.s | 7 |
2 files changed, 12 insertions, 0 deletions
diff --git a/lib/Target/X86/X86InstrInfo.td b/lib/Target/X86/X86InstrInfo.td index fb6c7a5fd3..bd0e86f941 100644 --- a/lib/Target/X86/X86InstrInfo.td +++ b/lib/Target/X86/X86InstrInfo.td @@ -1465,6 +1465,11 @@ def : InstAlias<"jmpw $seg, $off", (FARJMP16i i16imm:$off, i16imm:$seg)>; def : InstAlias<"calll $seg, $off", (FARCALL32i i32imm:$off, i16imm:$seg)>; def : InstAlias<"jmpl $seg, $off", (FARJMP32i i32imm:$off, i16imm:$seg)>; +// Force mov without a suffix with a segment and mem to prefer the 'l' form of +// the move. All segment/mem forms are equivalent, this has the shortest +// encoding. +def : InstAlias<"mov $mem, $seg", (MOV32sm SEGMENT_REG:$seg, i32mem:$mem)>; +def : InstAlias<"mov $seg, $mem", (MOV32ms i32mem:$mem, SEGMENT_REG:$seg)>; // Match 'movq <largeimm>, <reg>' as an alias for movabsq. def : InstAlias<"movq $imm, $reg", (MOV64ri GR64:$reg, i64imm:$imm)>; diff --git a/test/MC/X86/x86-64.s b/test/MC/X86/x86-64.s index 3df90217d8..6a24e39219 100644 --- a/test/MC/X86/x86-64.s +++ b/test/MC/X86/x86-64.s @@ -873,3 +873,10 @@ decl %eax // CHECK: decl %eax # encoding: [0xff,0xc8] // CHECK: sidt 4(%rax) // CHECK: encoding: [0x0f,0x01,0x48,0x04] sidtq 4(%rax) + + +// rdar://8208615 +mov (%rsi), %gs // CHECK: movl (%rsi), %gs # encoding: [0x8e,0x2e] +mov %gs, (%rsi) // CHECK: movl %gs, (%rsi) # encoding: [0x8c,0x2e] + + |