Replace the old algorithm that emitted the "print the alias for an instruction"

with the newer, cleaner model. It uses the IAPrinter class to hold the
information that is needed to match an instruction with its alias. This also
takes into account the available features of the platform.

There is one bit of ugliness. The way the logic determines if a pattern is
unique is O(N**2), which is gross. But in reality, the number of items it's
checking against isn't large. So while it's N**2, it shouldn't be a massive time
sink.

llvm-svn: 129110

1 files changed, 14 insertions, 1 deletions

diff --git a/llvm/lib/Target/X86/InstPrinter/X86ATTInstPrinter.cpp b/llvm/lib/Target/X86/InstPrinter/X86ATTInstPrinter.cpp
index d6950f49f82..d006eca3449 100644
--- a/llvm/lib/Target/X86/InstPrinter/X86ATTInstPrinter.cpp
+++ b/llvm/lib/Target/X86/InstPrinter/X86ATTInstPrinter.cpp
@@ -15,6 +15,7 @@
 #define DEBUG_TYPE "asm-printer"
 #include "X86ATTInstPrinter.h"
 #include "X86InstComments.h"
+#include "X86Subtarget.h"
 #include "llvm/MC/MCInst.h"
 #include "llvm/MC/MCAsmInfo.h"
 #include "llvm/MC/MCExpr.h"
@@ -22,11 +23,23 @@
 #include "llvm/Support/Format.h"
 #include "llvm/Support/FormattedStream.h"
 #include "X86GenInstrNames.inc"
+#include <map>
 using namespace llvm;
 
 // Include the auto-generated portion of the assembly writer.
 #define GET_INSTRUCTION_NAME
+#define PRINT_ALIAS_INSTR
+#include "X86GenRegisterNames.inc"
 #include "X86GenAsmWriter.inc"
+#undef PRINT_ALIAS_INSTR
+#undef GET_INSTRUCTION_NAME
+
+X86ATTInstPrinter::X86ATTInstPrinter(TargetMachine &TM, const MCAsmInfo &MAI)
+  : MCInstPrinter(MAI) {
+  // Initialize the set of available features.
+  setAvailableFeatures(ComputeAvailableFeatures(
+            &TM.getSubtarget<X86Subtarget>()));
+}
 
 void X86ATTInstPrinter::printInst(const MCInst *MI, raw_ostream &OS) {
   printInstruction(MI, OS);
@@ -35,11 +48,11 @@ void X86ATTInstPrinter::printInst(const MCInst *MI, raw_ostream &OS) {
   if (CommentStream)
     EmitAnyX86InstComments(MI, *CommentStream, getRegisterName);
 }
+
 StringRef X86ATTInstPrinter::getOpcodeName(unsigned Opcode) const {
   return getInstructionName(Opcode);
 }
 
-
 void X86ATTInstPrinter::printSSECC(const MCInst *MI, unsigned Op,
                                    raw_ostream &O) {
   switch (MI->getOperand(Op).getImm()) {