4 files changed, 46 insertions, 50 deletions
diff --git a/lib/Target/ARM/ARMInstrInfo.cpp b/lib/Target/ARM/ARMInstrInfo.cpp
index b8f607e..31b0c41 100644
--- a/lib/Target/ARM/ARMInstrInfo.cpp
+++ b/lib/Target/ARM/ARMInstrInfo.cpp
@@ -31,7 +31,8 @@ ARMInstrInfo::ARMInstrInfo(const ARMSubtarget &STI)
 /// getNoopForMachoTarget - Return the noop instruction to use for a noop.
 void ARMInstrInfo::getNoopForMachoTarget(MCInst &NopInst) const {
   if (hasNOP()) {
-    NopInst.setOpcode(ARM::NOP);
+    NopInst.setOpcode(ARM::HINT);
+    NopInst.addOperand(MCOperand::CreateImm(0));
     NopInst.addOperand(MCOperand::CreateImm(ARMCC::AL));
     NopInst.addOperand(MCOperand::CreateReg(0));
   } else {
diff --git a/lib/Target/ARM/ARMInstrInfo.td b/lib/Target/ARM/ARMInstrInfo.td
index 50ae826..5131152 100644
--- a/lib/Target/ARM/ARMInstrInfo.td
+++ b/lib/Target/ARM/ARMInstrInfo.td
@@ -1585,33 +1585,18 @@ def ATOMCMPXCHG6432 : PseudoInst<(outs GPR:$dst1, GPR:$dst2),
                                  NoItinerary, []>;
 }
 
-def NOP : AI<(outs), (ins), MiscFrm, NoItinerary, "nop", "", []>,
-          Requires<[IsARM, HasV6T2]> {
-  let Inst{27-16} = 0b001100100000;
-  let Inst{15-8} = 0b11110000;
-  let Inst{7-0} = 0b00000000;
-}
-
-def YIELD : AI<(outs), (ins), MiscFrm, NoItinerary, "yield", "", []>,
-          Requires<[IsARM, HasV6T2]> {
-  let Inst{27-16} = 0b001100100000;
-  let Inst{15-8} = 0b11110000;
-  let Inst{7-0} = 0b00000001;
+def HINT : AI<(outs), (ins imm0_255:$imm), MiscFrm, NoItinerary,
+              "hint", "\t$imm", []>, Requires<[IsARM, HasV6]> {
+  bits<8> imm;
+  let Inst{27-8} = 0b00110010000011110000;
+  let Inst{7-0} = imm;
 }
 
-def WFE : AI<(outs), (ins), MiscFrm, NoItinerary, "wfe", "", []>,
-          Requires<[IsARM, HasV6T2]> {
-  let Inst{27-16} = 0b001100100000;
-  let Inst{15-8} = 0b11110000;
-  let Inst{7-0} = 0b00000010;
-}
-
-def WFI : AI<(outs), (ins), MiscFrm, NoItinerary, "wfi", "", []>,
-          Requires<[IsARM, HasV6T2]> {
-  let Inst{27-16} = 0b001100100000;
-  let Inst{15-8} = 0b11110000;
-  let Inst{7-0} = 0b00000011;
-}
+def : InstAlias<"nop$p", (HINT 0, pred:$p)>, Requires<[IsARM, HasV6T2]>;
+def : InstAlias<"yield$p", (HINT 1, pred:$p)>, Requires<[IsARM, HasV6T2]>;
+def : InstAlias<"wfe$p", (HINT 2, pred:$p)>, Requires<[IsARM, HasV6T2]>;
+def : InstAlias<"wfi$p", (HINT 3, pred:$p)>, Requires<[IsARM, HasV6T2]>;
+def : InstAlias<"sev$p", (HINT 4, pred:$p)>, Requires<[IsARM, HasV6T2]>;
 
 def SEL : AI<(outs GPR:$Rd), (ins GPR:$Rn, GPR:$Rm), DPFrm, NoItinerary, "sel",
              "\t$Rd, $Rn, $Rm", []>, Requires<[IsARM, HasV6]> {
@@ -1624,18 +1609,10 @@ def SEL : AI<(outs GPR:$Rd), (ins GPR:$Rn, GPR:$Rm), DPFrm, NoItinerary, "sel",
   let Inst{27-20} = 0b01101000;
   let Inst{7-4} = 0b1011;
   let Inst{11-8} = 0b1111;
-  
   let Unpredictable{11-8} = 0b1111;
 }
 
-def SEV : AI<(outs), (ins), MiscFrm, NoItinerary, "sev", "",
-             []>, Requires<[IsARM, HasV6T2]> {
-  let Inst{27-16} = 0b001100100000;
-  let Inst{15-8} = 0b11110000;
-  let Inst{7-0} = 0b00000100;
-}
-
-// The i32imm operand $val can be used by a debugger to store more information
+// The 16-bit operand $val can be used by a debugger to store more information
 // about the breakpoint.
 def BKPT : AI<(outs), (ins imm0_65535:$val), MiscFrm, NoItinerary,
               "bkpt", "\t$val", []>, Requires<[IsARM]> {
diff --git a/lib/Target/ARM/ARMInstrThumb2.td b/lib/Target/ARM/ARMInstrThumb2.td
index d49b3ad..e780b8a 100644
--- a/lib/Target/ARM/ARMInstrThumb2.td
+++ b/lib/Target/ARM/ARMInstrThumb2.td
@@ -3457,21 +3457,18 @@ let imod = 0, iflags = 0, M = 1 in
 
 // A6.3.4 Branches and miscellaneous control
 // Table A6-14 Change Processor State, and hint instructions
-class T2I_hint<bits<8> op7_0, string opc, string asm>
-  : T2I<(outs), (ins), NoItinerary, opc, asm, []> {
-  let Inst{31-20} = 0xf3a;
-  let Inst{19-16} = 0b1111;
-  let Inst{15-14} = 0b10;
-  let Inst{12} = 0;
-  let Inst{10-8} = 0b000;
-  let Inst{7-0} = op7_0;
-}
-
-def t2NOP   : T2I_hint<0b00000000, "nop",   ".w">;
-def t2YIELD : T2I_hint<0b00000001, "yield", ".w">;
-def t2WFE   : T2I_hint<0b00000010, "wfe",   ".w">;
-def t2WFI   : T2I_hint<0b00000011, "wfi",   ".w">;
-def t2SEV   : T2I_hint<0b00000100, "sev",   ".w">;
+def t2HINT : T2I<(outs), (ins imm0_255:$imm), NoItinerary, "hint", "\t$imm",[]>{
+  bits<8> imm;
+  let Inst{31-8} = 0b111100111010111110000000;
+  let Inst{7-0} = imm;
+}
+
+def : t2InstAlias<"hint$p.w $imm", (t2HINT imm0_255:$imm, pred:$p)>;
+def : t2InstAlias<"nop$p.w", (t2HINT 0, pred:$p)>;
+def : t2InstAlias<"yield$p.w", (t2HINT 1, pred:$p)>;
+def : t2InstAlias<"wfe$p.w", (t2HINT 2, pred:$p)>;
+def : t2InstAlias<"wfi$p.w", (t2HINT 3, pred:$p)>;
+def : t2InstAlias<"sev$p.w", (t2HINT 4, pred:$p)>;
 
 def t2DBG : T2I<(outs), (ins imm0_15:$opt), NoItinerary, "dbg", "\t$opt", []> {
   bits<4> opt;
diff --git a/lib/Target/ARM/InstPrinter/ARMInstPrinter.cpp b/lib/Target/ARM/InstPrinter/ARMInstPrinter.cpp
index f0c7453..2f6b1b0 100644
--- a/lib/Target/ARM/InstPrinter/ARMInstPrinter.cpp
+++ b/lib/Target/ARM/InstPrinter/ARMInstPrinter.cpp
@@ -52,6 +52,27 @@ void ARMInstPrinter::printInst(const MCInst *MI, raw_ostream &O,
                                StringRef Annot) {
   unsigned Opcode = MI->getOpcode();
 
+  // Check for HINT instructions w/ canonical names.
+  if (Opcode == ARM::HINT || Opcode == ARM::t2HINT) {
+    switch (MI->getOperand(0).getImm()) {
+    case 0: O << "\tnop"; break;
+    case 1: O << "\tyield"; break;
+    case 2: O << "\twfe"; break;
+    case 3: O << "\twfi"; break;
+    case 4: O << "\tsev"; break;
+    default:
+      // Anything else should just print normally.
+      printInstruction(MI, O);
+      printAnnotation(O, Annot);
+      return;
+    }
+    printPredicateOperand(MI, 1, O);
+    if (Opcode == ARM::t2HINT)
+      O << ".w";
+    printAnnotation(O, Annot);
+    return;
+  }
+
   // Check for MOVs and print canonical forms, instead.
   if (Opcode == ARM::MOVsr) {
     // FIXME: Thumb variants?