Post process ADC/SBB and use a shorter encoding if they use a sign extended immediate.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177243 91177308-0d34-0410-b5e6-96231b3b80d8

Author: topperc

lib/Target/X86/AsmParser/X86AsmParser.cpp

@@ -1801,6 +1801,12 @@ processInstruction(MCInst &Inst,
   case X86::SUB16i16: return convert16i16to16ri8(Inst, X86::SUB16ri8);
   case X86::SUB32i32: return convert32i32to32ri8(Inst, X86::SUB32ri8);
   case X86::SUB64i32: return convert64i32to64ri8(Inst, X86::SUB64ri8);
+  case X86::ADC16i16: return convert16i16to16ri8(Inst, X86::ADC16ri8);
+  case X86::ADC32i32: return convert32i32to32ri8(Inst, X86::ADC32ri8);
+  case X86::ADC64i32: return convert64i32to64ri8(Inst, X86::ADC64ri8);
+  case X86::SBB16i16: return convert16i16to16ri8(Inst, X86::SBB16ri8);
+  case X86::SBB32i32: return convert32i32to32ri8(Inst, X86::SBB32ri8);
+  case X86::SBB64i32: return convert64i32to64ri8(Inst, X86::SBB64ri8);
   }
 }
 

test/MC/X86/intel-syntax-encoding.s

@@ -31,6 +31,20 @@
 // CHECK: encoding: [0x48,0x83,0xc0,0xf4]
 	add	rax, -12
 
+// CHECK: encoding: [0x66,0x83,0xd0,0xf4]
+	adc	ax, -12
+// CHECK: encoding: [0x83,0xd0,0xf4]
+	adc	eax, -12
+// CHECK: encoding: [0x48,0x83,0xd0,0xf4]
+	adc	rax, -12
+
+// CHECK: encoding: [0x66,0x83,0xd8,0xf4]
+	sbb	ax, -12
+// CHECK: encoding: [0x83,0xd8,0xf4]
+	sbb	eax, -12
+// CHECK: encoding: [0x48,0x83,0xd8,0xf4]
+	sbb	rax, -12
+
 // CHECK: encoding: [0x66,0x83,0xf8,0xf4]
 	cmp	ax, -12
 // CHECK: encoding: [0x83,0xf8,0xf4]