-; RUN: llc -mtriple=i386-linux-gnu %s -o - | FileCheck %s
-; RUN: llc -mtriple=x86_64-linux-gnu -mattr=+sahf %s -o - | FileCheck %s
+; RUN: llc -mtriple=i386-linux-gnu %s -o - | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK32
+; RUN: llc -mtriple=x86_64-linux-gnu -mattr=+sahf %s -o - | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK64
; TODO: Reenable verify-machineinstrs once the if (!AXDead) // FIXME in
; X86InstrInfo::copyPhysReg() is resolved.
; CHECK: cmpxchg
; CHECK: seto %al
; CHECK-NEXT: lahf
-; Save result of the first cmpxchg into D.
-; CHECK-NEXT: mov{{[lq]}} %[[AX:[er]ax]], %[[D:[re]d[xi]]]
+; Save result of the first cmpxchg into a temporary.
+; For 32-bit ISA, EDX, EAX are used by the results.
+; EAX, EBX, ECX, and EDX are used to set the arguments.
+; That leaves us EDI and ESI.
+; CHECK32-NEXT: movl %[[AX:eax]], %[[TMP:e[ds]i]]
+; For 64-bit ISA, RAX is used for both the result and argument.
+; This leaves us plenty of choices for the temporary. For now,
+; this is rdx, but any register could do.
+; CHECK64-NEXT: mov{{[lq]}} %[[AX:[er]ax]], %[[TMP:rdx]]
; CHECK: cmpxchg
; CHECK-NEXT: sete %al
; Save result of the second cmpxchg onto the stack.
; CHECK-NEXT: push{{[lq]}} %[[AX]]
; Restore result of the first cmpxchg from D, put it back in EFLAGS.
-; CHECK-NEXT: mov{{[lq]}} %[[D]], %[[AX]]
+; CHECK-NEXT: mov{{[lq]}} %[[TMP]], %[[AX]]
; CHECK-NEXT: addb $127, %al
; CHECK-NEXT: sahf
; Restore result of the second cmpxchg from the stack.