Use getRegForInlineAsmConstraint instead of custom defining regclasses
via vectors.

Part of rdar://9643582


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134079 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index b327f1b..4f8b90f 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -12875,60 +12875,6 @@
   return TargetLowering::LowerAsmOperandForConstraint(Op, Constraint, Ops, DAG);
 }
 
-std::vector<unsigned> X86TargetLowering::
-getRegClassForInlineAsmConstraint(const std::string &Constraint,
-                                  EVT VT) const {
-  if (Constraint.size() == 1) {
-    // FIXME: not handling fp-stack yet!
-    switch (Constraint[0]) {      // GCC X86 Constraint Letters
-    default: break;  // Unknown constraint letter
-    case 'q':   // GENERAL_REGS in 64-bit mode, Q_REGS in 32-bit mode.
-      if (Subtarget->is64Bit()) {
-        if (VT == MVT::i32)
-          return make_vector<unsigned>(X86::EAX, X86::EDX, X86::ECX, X86::EBX,
-                                       X86::ESI, X86::EDI, X86::R8D, X86::R9D,
-                                       X86::R10D,X86::R11D,X86::R12D,
-                                       X86::R13D,X86::R14D,X86::R15D,
-                                       X86::EBP, X86::ESP, 0);
-        else if (VT == MVT::i16)
-          return make_vector<unsigned>(X86::AX,  X86::DX,  X86::CX, X86::BX,
-                                       X86::SI,  X86::DI,  X86::R8W,X86::R9W,
-                                       X86::R10W,X86::R11W,X86::R12W,
-                                       X86::R13W,X86::R14W,X86::R15W,
-                                       X86::BP,  X86::SP, 0);
-        else if (VT == MVT::i8)
-          return make_vector<unsigned>(X86::AL,  X86::DL,  X86::CL, X86::BL,
-                                       X86::SIL, X86::DIL, X86::R8B,X86::R9B,
-                                       X86::R10B,X86::R11B,X86::R12B,
-                                       X86::R13B,X86::R14B,X86::R15B,
-                                       X86::BPL, X86::SPL, 0);
-
-        else if (VT == MVT::i64)
-          return make_vector<unsigned>(X86::RAX, X86::RDX, X86::RCX, X86::RBX,
-                                       X86::RSI, X86::RDI, X86::R8,  X86::R9,
-                                       X86::R10, X86::R11, X86::R12,
-                                       X86::R13, X86::R14, X86::R15,
-                                       X86::RBP, X86::RSP, 0);
-
-        break;
-      }
-      // 32-bit fallthrough
-    case 'Q':   // Q_REGS
-      if (VT == MVT::i32)
-        return make_vector<unsigned>(X86::EAX, X86::EDX, X86::ECX, X86::EBX, 0);
-      else if (VT == MVT::i16)
-        return make_vector<unsigned>(X86::AX, X86::DX, X86::CX, X86::BX, 0);
-      else if (VT == MVT::i8)
-        return make_vector<unsigned>(X86::AL, X86::DL, X86::CL, X86::BL, 0);
-      else if (VT == MVT::i64)
-        return make_vector<unsigned>(X86::RAX, X86::RDX, X86::RCX, X86::RBX, 0);
-      break;
-    }
-  }
-
-  return std::vector<unsigned>();
-}
-
 std::pair<unsigned, const TargetRegisterClass*>
 X86TargetLowering::getRegForInlineAsmConstraint(const std::string &Constraint,
                                                 EVT VT) const {
@@ -12938,6 +12884,32 @@
     // GCC Constraint Letters
     switch (Constraint[0]) {
     default: break;
+      // TODO: Slight differences here in allocation order and leaving
+      // RIP in the class. Do they matter any more here than they do
+      // in the normal allocation?
+    case 'q':   // GENERAL_REGS in 64-bit mode, Q_REGS in 32-bit mode.
+      if (Subtarget->is64Bit()) {
+	if (VT == MVT::i32)
+	  return std::make_pair(0U, X86::GR32RegisterClass);
+	else if (VT == MVT::i16)
+	  return std::make_pair(0U, X86::GR16RegisterClass);
+	else if (VT == MVT::i8)
+	  return std::make_pair(0U, X86::GR8RegisterClass);
+	else if (VT == MVT::i64)
+	  return std::make_pair(0U, X86::GR64RegisterClass);
+	break;
+      }
+      // 32-bit fallthrough
+    case 'Q':   // Q_REGS
+      if (VT == MVT::i32)
+	return std::make_pair(0U, X86::GR32_ABCDRegisterClass);
+      else if (VT == MVT::i16)
+	return std::make_pair(0U, X86::GR16_ABCDRegisterClass);
+      else if (VT == MVT::i8)
+	return std::make_pair(0U, X86::GR8_ABCD_LRegisterClass);
+      else if (VT == MVT::i64)
+	return std::make_pair(0U, X86::GR64_ABCDRegisterClass);
+      break;
     case 'r':   // GENERAL_REGS
     case 'l':   // INDEX_REGS
       if (VT == MVT::i8)