gas accepts xchg <mem>, <reg> as a synonym for xchg <reg>, <mem>.
Add this to the mc assembler, fixing PR8061
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113346 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/AsmParser/X86AsmParser.cpp b/lib/Target/X86/AsmParser/X86AsmParser.cpp
index cddf8eb..58e4554 100644
--- a/lib/Target/X86/AsmParser/X86AsmParser.cpp
+++ b/lib/Target/X86/AsmParser/X86AsmParser.cpp
@@ -753,6 +753,7 @@
PatchedName = "vpclmulqdq";
}
}
+
Operands.push_back(X86Operand::CreateToken(PatchedName, NameLoc));
if (ExtraImmOp)
@@ -827,6 +828,16 @@
delete Operands[0];
Operands[0] = X86Operand::CreateToken("sldtw", NameLoc);
}
+
+ // The assembler accepts "xchgX <reg>, <mem>" and "xchgX <mem>, <reg>" as
+ // synonyms. Our tables only have the "<reg>, <mem>" form, so if we see the
+ // other operand order, swap them.
+ if (Name == "xchgb" || Name == "xchgw" || Name == "xchgl" || Name == "xchgq")
+ if (Operands.size() == 3 &&
+ static_cast<X86Operand*>(Operands[1])->isMem() &&
+ static_cast<X86Operand*>(Operands[2])->isReg()) {
+ std::swap(Operands[1], Operands[2]);
+ }
return false;
}