[llvm-commits] [llvm] r138269 - in /llvm/trunk: lib/Target/ARM/ARMInstrVFP.td lib/Target/ARM/Disassembler/ARMDisassembler.cpp test/MC/Disassembler/ARM/neon.txt

[Owen Anderson]

Author: resistor
Date: Mon Aug 22 15:27:12 2011
New Revision: 138269

URL: http://llvm.org/viewvc/llvm-project?rev=138269&view=rev
Log:
Fix decoding of VMOVSRR and VMOVRRS, which account for the overwhelming majority of decoder crashes detected by randomized testing.

Modified:
    llvm/trunk/lib/Target/ARM/ARMInstrVFP.td
    llvm/trunk/lib/Target/ARM/Disassembler/ARMDisassembler.cpp
    llvm/trunk/test/MC/Disassembler/ARM/neon.txt

Modified: llvm/trunk/lib/Target/ARM/ARMInstrVFP.td
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMInstrVFP.td?rev=138269&r1=138268&r2=138269&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMInstrVFP.td (original)
+++ llvm/trunk/lib/Target/ARM/ARMInstrVFP.td Mon Aug 22 15:27:12 2011
@@ -521,6 +521,7 @@
   // Some single precision VFP instructions may be executed on both NEON and VFP
   // pipelines.
   let D = VFPNeonDomain;
+  let DecoderMethod = "DecodeVMOVRRS";
 }
 } // neverHasSideEffects
 
@@ -559,6 +560,8 @@
   // Some single precision VFP instructions may be executed on both NEON and VFP
   // pipelines.
   let D = VFPNeonDomain;
+
+  let DecoderMethod = "DecodeVMOVSRR";
 }
 
 // FMRDH: SPR -> GPR

Modified: llvm/trunk/lib/Target/ARM/Disassembler/ARMDisassembler.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/Disassembler/ARMDisassembler.cpp?rev=138269&r1=138268&r2=138269&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/Disassembler/ARMDisassembler.cpp (original)
+++ llvm/trunk/lib/Target/ARM/Disassembler/ARMDisassembler.cpp Mon Aug 22 15:27:12 2011
@@ -175,6 +175,10 @@
                                uint64_t Address, const void *Decoder);
 static DecodeStatus DecodeVST4LN(llvm::MCInst &Inst, unsigned Insn,
                                uint64_t Address, const void *Decoder);
+static DecodeStatus DecodeVMOVSRR(llvm::MCInst &Inst, unsigned Insn,
+                               uint64_t Address, const void *Decoder);
+static DecodeStatus DecodeVMOVRRS(llvm::MCInst &Inst, unsigned Insn,
+                               uint64_t Address, const void *Decoder);
 
 
 static DecodeStatus DecodeThumbAddSpecialReg(llvm::MCInst &Inst, uint16_t Insn,
@@ -3195,3 +3199,44 @@
   return S;
 }
 
+static DecodeStatus DecodeVMOVSRR(llvm::MCInst &Inst, unsigned Insn,
+                                  uint64_t Address, const void *Decoder) {
+  DecodeStatus S = Success;
+  unsigned Rt  = fieldFromInstruction32(Insn, 12, 4);
+  unsigned Rt2 = fieldFromInstruction32(Insn, 16, 4);
+  unsigned Rm  = fieldFromInstruction32(Insn,  0, 4);
+  unsigned pred = fieldFromInstruction32(Insn, 28, 4);
+  Rm |= fieldFromInstruction32(Insn, 5, 1) << 4;
+
+  if (Rt == 0xF || Rt2 == 0xF || Rm == 0x1F)
+    CHECK(S, Unpredictable);
+
+  CHECK(S, DecodeSPRRegisterClass(Inst, Rm  , Address, Decoder));
+  CHECK(S, DecodeSPRRegisterClass(Inst, Rm+1, Address, Decoder));
+  CHECK(S, DecodeGPRRegisterClass(Inst, Rt  , Address, Decoder));
+  CHECK(S, DecodeGPRRegisterClass(Inst, Rt2 , Address, Decoder));
+  CHECK(S, DecodePredicateOperand(Inst, pred, Address, Decoder));
+
+  return S;
+}
+
+static DecodeStatus DecodeVMOVRRS(llvm::MCInst &Inst, unsigned Insn,
+                                  uint64_t Address, const void *Decoder) {
+  DecodeStatus S = Success;
+  unsigned Rt  = fieldFromInstruction32(Insn, 12, 4);
+  unsigned Rt2 = fieldFromInstruction32(Insn, 16, 4);
+  unsigned Rm  = fieldFromInstruction32(Insn,  0, 4);
+  unsigned pred = fieldFromInstruction32(Insn, 28, 4);
+  Rm |= fieldFromInstruction32(Insn, 5, 1) << 4;
+
+  if (Rt == 0xF || Rt2 == 0xF || Rm == 0x1F)
+    CHECK(S, Unpredictable);
+
+  CHECK(S, DecodeGPRRegisterClass(Inst, Rt  , Address, Decoder));
+  CHECK(S, DecodeGPRRegisterClass(Inst, Rt2 , Address, Decoder));
+  CHECK(S, DecodeSPRRegisterClass(Inst, Rm  , Address, Decoder));
+  CHECK(S, DecodeSPRRegisterClass(Inst, Rm+1, Address, Decoder));
+  CHECK(S, DecodePredicateOperand(Inst, pred, Address, Decoder));
+
+  return S;
+}

Modified: llvm/trunk/test/MC/Disassembler/ARM/neon.txt
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/MC/Disassembler/ARM/neon.txt?rev=138269&r1=138268&r2=138269&view=diff
==============================================================================
--- llvm/trunk/test/MC/Disassembler/ARM/neon.txt (original)
+++ llvm/trunk/test/MC/Disassembler/ARM/neon.txt Mon Aug 22 15:27:12 2011
@@ -1851,3 +1851,5 @@
 0x0d 0x03 0x80 0xf4
 # CHECK: vst4.8	{d0[0], d1[0], d2[0], d3[0]}, [r0]!
 
+0x3d 0x2a 0x5e 0x6c
+# CHECK: vmovvs	r2, lr, s29, s30