Add code to emulate STRB (Thumb) instruction.
git-svn-id: https://llvm.org/svn/llvm-project/llvdb/trunk@125686 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/source/Plugins/Instruction/ARM/EmulateInstructionARM.cpp b/source/Plugins/Instruction/ARM/EmulateInstructionARM.cpp
index b2695cf..bacdd08 100644
--- a/source/Plugins/Instruction/ARM/EmulateInstructionARM.cpp
+++ b/source/Plugins/Instruction/ARM/EmulateInstructionARM.cpp
@@ -3963,6 +3963,144 @@
}
return true;
}
+
+bool
+EmulateInstructionARM::EmulateSTRBThumb (ARMEncoding encoding)
+{
+#if 0
+ if ConditionPassed() then
+ EncodingSpecificOperations(); NullCheckIfThumbEE(n);
+ offset_addr = if add then (R[n] + imm32) else (R[n] - imm32);
+ address = if index then offset_addr else R[n];
+ MemU[address,1] = R[t]<7:0>;
+ if wback then R[n] = offset_addr;
+#endif
+
+
+ bool success = false;
+ const uint32_t opcode = OpcodeAsUnsigned (&success);
+ if (!success)
+ return false;
+
+ if (ConditionPassed ())
+ {
+ uint32_t t;
+ uint32_t n;
+ uint32_t imm32;
+ bool index;
+ bool add;
+ bool wback;
+ // EncodingSpecificOperations(); NullCheckIfThumbEE(n);
+ switch (encoding)
+ {
+ case eEncodingT1:
+ // t = UInt(Rt); n = UInt(Rn); imm32 = ZeroExtend(imm5, 32);
+ t = Bits32 (opcode, 2, 0);
+ n = Bits32 (opcode, 5, 3);
+ imm32 = Bits32 (opcode, 10, 6);
+
+ // index = TRUE; add = TRUE; wback = FALSE;
+ index = true;
+ add = true;
+ wback = false;
+ break;
+
+ case eEncodingT2:
+ // if Rn == ’1111’ then UNDEFINED;
+ if (Bits32 (opcode, 19, 16) == 15)
+ return false;
+
+ // t = UInt(Rt); n = UInt(Rn); imm32 = ZeroExtend(imm12, 32);
+ t = Bits32 (opcode, 15, 12);
+ n = Bits32 (opcode, 19, 16);
+ imm32 = Bits32 (opcode, 11, 0);
+
+ // index = TRUE; add = TRUE; wback = FALSE;
+ index = true;
+ add = true;
+ wback = false;
+
+ // if BadReg(t) then UNPREDICTABLE;
+ if (BadReg (t))
+ return false;
+ break;
+
+ case eEncodingT3:
+ // if P == ’1’ && U == ’1’ && W == ’0’ then SEE STRBT;
+ // if Rn == ’1111’ || (P == ’0’ && W == ’0’) then UNDEFINED;
+ if (Bits32 (opcode, 19, 16) == 15)
+ return false;
+
+ // t = UInt(Rt); n = UInt(Rn); imm32 = ZeroExtend(imm8, 32);
+ t = Bits32 (opcode, 15, 12);
+ n = Bits32 (opcode, 19, 16);
+ imm32 = Bits32 (opcode, 7, 0);
+
+ // index = (P == ’1’); add = (U == ’1’); wback = (W == ’1’);
+ index = BitIsSet (opcode, 10);
+ add = BitIsSet (opcode, 9);
+ wback = BitIsSet (opcode, 8);
+
+ // if BadReg(t) || (wback && n == t) then UNPREDICTABLE
+ if ((BadReg (t)) || (wback && (n == t)))
+ return false;
+ break;
+
+ default:
+ return false;
+ }
+
+ addr_t offset_addr;
+ addr_t address;
+ addr_t base_address = ReadRegisterUnsigned (eRegisterKindDWARF, dwarf_r0 + n, 0, &success);
+ if (!success)
+ return false;
+
+ // offset_addr = if add then (R[n] + imm32) else (R[n] - imm32);
+ if (add)
+ offset_addr = base_address + imm32;
+ else
+ offset_addr = base_address - imm32;
+
+ // address = if index then offset_addr else R[n];
+ if (index)
+ address = offset_addr;
+ else
+ address = base_address;
+
+ // MemU[address,1] = R[t]<7:0>; NOTE: "MemU' means UNALIGNED memory access
+ Register base_reg;
+ base_reg.SetRegister (eRegisterKindDWARF, dwarf_r0 + n);
+
+ Register data_reg;
+ data_reg.SetRegister (eRegisterKindDWARF, dwarf_r0 + t);
+
+ EmulateInstruction::Context context;
+ context.type = eContextRegisterStore;
+ context.SetRegisterToRegisterPlusOffset (data_reg, base_reg, address - base_address);
+
+ uint32_t data = ReadRegisterUnsigned (eRegisterKindDWARF, dwarf_r0 + t, 0, &success);
+ if (!success)
+ return false;
+
+ data = Bits32 (data, 7, 0);
+
+ if (!WriteMemoryUnsigned (context, address, data, 1))
+ return false;
+
+ // if wback then R[n] = offset_addr;
+ if (wback)
+ {
+ context.type = eContextRegisterLoad;
+ context.SetAddress (offset_addr);
+ if (!WriteRegisterUnsigned (context, eRegisterKindDWARF, dwarf_r0 + n, offset_addr))
+ return false;
+ }
+
+ }
+
+ return true;
+}
EmulateInstructionARM::ARMOpcode*
EmulateInstructionARM::GetARMOpcodeForInstruction (const uint32_t opcode)
@@ -4205,7 +4343,10 @@
{ 0xfff00000, 0xf8c00000, ARMV6T2_ABOVE, eEncodingT3, eSize32, &EmulateInstructionARM::EmulateSTRThumb, "str<c>.w <Rt [<Rn>,#<imm12>]" },
{ 0xfff00800, 0xf8400800, ARMV6T2_ABOVE, eEncodingT4, eSize32, &EmulateInstructionARM::EmulateSTRThumb, "str<c> <Rt> [<Rn>,#+/-<imm8>]" },
{ 0xfffffe00, 0x00005000, ARMV4T_ABOVE, eEncodingT1, eSize16, &EmulateInstructionARM::EmulateSTRRegister, "str<c> <Rt> {<Rn> <Rm>]" },
- { 0xfff00fc0, 0xf8400000, ARMV6T2_ABOVE, eEncodingT2, eSize32, &EmulateInstructionARM::EmulateSTRRegister, "str<c>.w <Rt> [<Rn> <Rm> {lsl #imm2>}]" }
+ { 0xfff00fc0, 0xf8400000, ARMV6T2_ABOVE, eEncodingT2, eSize32, &EmulateInstructionARM::EmulateSTRRegister, "str<c>.w <Rt> [<Rn> <Rm> {lsl #imm2>}]" },
+ { 0xfffff800, 0x00007000, ARMV4T_ABOVE, eEncodingT1, eSize16, &EmulateInstructionARM::EmulateSTRBThumb, "strb<c> <Rt> [<Rn> #<imm5>]" },
+ { 0xfff00000, 0xf8800000, ARMV6T2_ABOVE, eEncodingT2, eSize32, &EmulateInstructionARM::EmulateSTRBThumb, "strb<c>.w <Rt> [<Rn> #<imm12>]" },
+ { 0xfff00800, 0xf8000800, ARMV6T2_ABOVE, eEncodingT3, eSize32, &EmulateInstructionARM::EmulateSTRBThumb, "strb<c> <Rt> [<Rn>, #+/-<imm8>]{!}" }
};
const size_t k_num_thumb_opcodes = sizeof(g_thumb_opcodes)/sizeof(ARMOpcode);