add various broken forms of fnstsw. I didn't add the %rax
version because it adds a prefix and makes even less sense
than the other broken forms. This wraps up rdar://8431422
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113932 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/AsmParser/X86AsmParser.cpp b/lib/Target/X86/AsmParser/X86AsmParser.cpp
index c21fc7a..7098c58 100644
--- a/lib/Target/X86/AsmParser/X86AsmParser.cpp
+++ b/lib/Target/X86/AsmParser/X86AsmParser.cpp
@@ -943,6 +943,25 @@
NameLoc, NameLoc));
}
+ // The assembler accepts various amounts of brokenness for fnstsw.
+ if (Name == "fnstsw") {
+ if (Operands.size() == 2 &&
+ static_cast<X86Operand*>(Operands[1])->isReg()) {
+ // "fnstsw al" and "fnstsw eax" -> "fnstw"
+ unsigned Reg = static_cast<X86Operand*>(Operands[1])->Reg.RegNo;
+ if (Reg == MatchRegisterName("eax") ||
+ Reg == MatchRegisterName("al")) {
+ delete Operands[1];
+ Operands.pop_back();
+ }
+ }
+
+ // "fnstw" -> "fnstw %ax"
+ if (Operands.size() == 1)
+ Operands.push_back(X86Operand::CreateReg(MatchRegisterName("ax"),
+ NameLoc, NameLoc));
+ }
+
return false;
}