fix some bugs in the alias support, unblocking changing of "clr" aliases

from c++ hacks to proper .td InstAlias definitions.  Change them!

llvm-svn: 118330

2 files changed, 6 insertions, 11 deletions

diff --git a/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp b/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp
index e57e34fb457..30d3a7e6c5a 100644
--- a/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp
+++ b/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp
@@ -983,17 +983,6 @@ ParseInstruction(StringRef Name, SMLoc NameLoc,
     Operands[0] = X86Operand::CreateToken("fstps", NameLoc);
   }
 
-
-  // "clr <reg>" -> "xor <reg>, <reg>".
-  if ((Name == "clrb" || Name == "clrw" || Name == "clrl" || Name == "clrq" ||
-       Name == "clr") && Operands.size() == 2 &&
-      static_cast<X86Operand*>(Operands[1])->isReg()) {
-    unsigned RegNo = static_cast<X86Operand*>(Operands[1])->getReg();
-    Operands.push_back(X86Operand::CreateReg(RegNo, NameLoc, NameLoc));
-    delete Operands[0];
-    Operands[0] = X86Operand::CreateToken("xor", NameLoc);
-  }
-
   // FIXME: Hack to handle recognize "aa[dm]" -> "aa[dm] $0xA".
   if ((Name.startswith("aad") || Name.startswith("aam")) &&
       Operands.size() == 1) {
diff --git a/llvm/lib/Target/X86/X86InstrInfo.td b/llvm/lib/Target/X86/X86InstrInfo.td
index ad3fe1556be..fdb17a13724 100644
--- a/llvm/lib/Target/X86/X86InstrInfo.td
+++ b/llvm/lib/Target/X86/X86InstrInfo.td
@@ -1370,6 +1370,12 @@ defm : IntegerCondCodeMnemonicAlias<"cmov", "q">;
 // Assembler Instruction Aliases
 //===----------------------------------------------------------------------===//
 
+// clr aliases.
+def : InstAlias<"clrb $reg", (XOR8rr  GR8 :$reg, GR8 :$reg)>;
+def : InstAlias<"clrw $reg", (XOR16rr GR16:$reg, GR16:$reg)>;
+def : InstAlias<"clrl $reg", (XOR32rr GR32:$reg, GR32:$reg)>;
+def : InstAlias<"clrq $reg", (XOR64rr GR64:$reg, GR64:$reg)>;
+
 // movsx aliases
 def : InstAlias<"movsx $src, $dst",
                 (MOVSX16rr8W GR16:$dst, GR8:$src)>;