Fix a typo in the handling of PKHTB opcode, plus add sanity check for illegal register

encodings for DisassembleArithMiscFrm().

rdar://problem/9238659

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128958 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/ARM/Disassembler/ARMDisassemblerCore.cpp b/lib/Target/ARM/Disassembler/ARMDisassemblerCore.cpp
index 58f9c1f..8c89505 100644 (file)
--- a/lib/Target/ARM/Disassembler/ARMDisassemblerCore.cpp
+++ b/lib/Target/ARM/Disassembler/ARMDisassemblerCore.cpp
@@ -1474,6 +1474,12 @@ static bool DisassembleArithMiscFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
 
   bool ThreeReg = NumOps > 2 && OpInfo[2].RegClass == ARM::GPRRegClassID;
 
+  // Sanity check the registers, which should not be 15.
+  if (decodeRd(insn) == 15 || decodeRm(insn) == 15)
+    return false;
+  if (ThreeReg && decodeRn(insn) == 15)
+    return false;
+
   MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
                                                      decodeRd(insn))));
   ++OpIdx;
@@ -1498,7 +1504,7 @@ static bool DisassembleArithMiscFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
     ARM_AM::ShiftOpc Opc = ARM_AM::no_shift;
     if (Opcode == ARM::PKHBT)
       Opc = ARM_AM::lsl;
-    else if (Opcode == ARM::PKHBT)
+    else if (Opcode == ARM::PKHTB)
       Opc = ARM_AM::asr;
     getImmShiftSE(Opc, ShiftAmt);
     MI.addOperand(MCOperand::CreateImm(ARM_AM::getSORegOpc(Opc, ShiftAmt)));

diff --git a/test/MC/Disassembler/ARM/arm-tests.txt b/test/MC/Disassembler/ARM/arm-tests.txt
index 084fc8b..3dabb7a 100644 (file)
--- a/test/MC/Disassembler/ARM/arm-tests.txt
+++ b/test/MC/Disassembler/ARM/arm-tests.txt
@@ -76,9 +76,12 @@
 # CHECK:       pkhbt   r8, r9, r10, lsl #4
 0x1a 0x82 0x89 0xe6
 
-# CHECK-NOT:   pkhbtls pc, r11, r11, lsl #0
-# CHECK:       pkhbtls pc, r11, r11
-0x1b 0xf0 0x8b 0x96
+# CHECK-NOT:   pkhbtls r10, r11, r11, lsl #0
+# CHECK:       pkhbtls r10, r11, r11
+0x1b 0xa0 0x8b 0x96
+
+# CHECK:       pkhtbmi lr, r1, r6, asr #21
+0xd6 0xea 0x81 0x46
 
 # CHECK:       pop     {r0, r2, r4, r6, r8, r10}
 0x55 0x05 0xbd 0xe8