[llvm-commits] [llvm] r155565 - in /llvm/trunk/lib/Target/ARM: AsmParser/ARMAsmParser.cpp MCTargetDesc/ARMMCCodeEmitter.cpp

[Richard Barton]

Author: rbarton
Date: Wed Apr 25 13:00:18 2012
New Revision: 155565

URL: http://llvm.org/viewvc/llvm-project?rev=155565&view=rev
Log:
Unify internal representation of ARM instructions with a register right-shifted by #32. These are stored as shifts by #0 in the MCInst and correctly marshalled when transforming from or to assembly representation.

Modified:
    llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
    llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMMCCodeEmitter.cpp

Modified: llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp?rev=155565&r1=155564&r2=155565&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp (original)
+++ llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp Wed Apr 25 13:00:18 2012
@@ -1446,8 +1446,10 @@
     assert(isRegShiftedImm() &&
            "addRegShiftedImmOperands() on non RegShiftedImm!");
     Inst.addOperand(MCOperand::CreateReg(RegShiftedImm.SrcReg));
+    // Shift of #32 is encoded as 0 where permitted
+    unsigned Imm = (RegShiftedImm.ShiftImm == 32 ? 0 : RegShiftedImm.ShiftImm);
     Inst.addOperand(MCOperand::CreateImm(
-      ARM_AM::getSORegOpc(RegShiftedImm.ShiftTy, RegShiftedImm.ShiftImm)));
+      ARM_AM::getSORegOpc(RegShiftedImm.ShiftTy, Imm)));
   }
 
   void addShifterImmOperands(MCInst &Inst, unsigned N) const {
@@ -6809,6 +6811,9 @@
     // A shift by zero is a plain MOVr, not a MOVsi.
     unsigned Amt = Inst.getOperand(2).getImm();
     unsigned Opc = Amt == 0 ? ARM::MOVr : ARM::MOVsi;
+    // A shift by 32 should be encoded as 0 when permitted
+    if (Amt == 32 && (ShiftTy == ARM_AM::lsr || ShiftTy == ARM_AM::asr))
+      Amt = 0;
     unsigned Shifter = ARM_AM::getSORegOpc(ShiftTy, Amt);
     MCInst TmpInst;
     TmpInst.setOpcode(Opc);
@@ -7154,7 +7159,9 @@
   }
   case ARM::MOVsi: {
     ARM_AM::ShiftOpc SOpc = ARM_AM::getSORegShOp(Inst.getOperand(2).getImm());
-    if (SOpc == ARM_AM::rrx) return false;
+    // rrx shifts and asr/lsr of #32 is encoded as 0
+    if (SOpc == ARM_AM::rrx || SOpc == ARM_AM::asr || SOpc == ARM_AM::lsr) 
+      return false;
     if (ARM_AM::getSORegOffset(Inst.getOperand(2).getImm()) == 0) {
       // Shifting by zero is accepted as a vanilla 'MOVr'
       MCInst TmpInst;

Modified: llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMMCCodeEmitter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMMCCodeEmitter.cpp?rev=155565&r1=155564&r2=155565&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMMCCodeEmitter.cpp (original)
+++ llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMMCCodeEmitter.cpp Wed Apr 25 13:00:18 2012
@@ -1192,8 +1192,7 @@
   // Encode shift_imm bit[11:7].
   Binary |= SBits << 4;
   unsigned Offset = ARM_AM::getSORegOffset(MO1.getImm());
-  assert(Offset && "Offset must be in range 1-32!");
-  if (Offset == 32) Offset = 0;
+  assert(Offset < 32 && "Offset must be in range 0-31!");
   return Binary | (Offset << 7);
 }