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-rw-r--r--ARMeilleure/Decoders/OpCode32.cs16
-rw-r--r--ARMeilleure/Decoders/OpCodeT32BImm20.cs29
-rw-r--r--ARMeilleure/Decoders/OpCodeT32BImm24.cs35
-rw-r--r--ARMeilleure/Decoders/OpCodeTable.cs4
4 files changed, 83 insertions, 1 deletions
diff --git a/ARMeilleure/Decoders/OpCode32.cs b/ARMeilleure/Decoders/OpCode32.cs
index 0d8ad1fd..92487c6e 100644
--- a/ARMeilleure/Decoders/OpCode32.cs
+++ b/ARMeilleure/Decoders/OpCode32.cs
@@ -13,11 +13,25 @@ namespace ARMeilleure.Decoders
Cond = (Condition)((uint)opCode >> 28);
}
+ public bool IsThumb()
+ {
+ return this is OpCodeT16 || this is OpCodeT32;
+ }
+
public uint GetPc()
{
// Due to backwards compatibility and legacy behavior of ARMv4 CPUs pipeline,
// the PC actually points 2 instructions ahead.
- return (uint)Address + (uint)OpCodeSizeInBytes * 2;
+ if (IsThumb())
+ {
+ // PC is ahead by 4 in thumb mode whether or not the current instruction
+ // is 16 or 32 bit.
+ return (uint)Address + 4u;
+ }
+ else
+ {
+ return (uint)Address + 8u;
+ }
}
}
} \ No newline at end of file
diff --git a/ARMeilleure/Decoders/OpCodeT32BImm20.cs b/ARMeilleure/Decoders/OpCodeT32BImm20.cs
new file mode 100644
index 00000000..8ed4b4b1
--- /dev/null
+++ b/ARMeilleure/Decoders/OpCodeT32BImm20.cs
@@ -0,0 +1,29 @@
+using ARMeilleure.Instructions;
+
+namespace ARMeilleure.Decoders
+{
+ class OpCodeT32BImm20 : OpCodeT32, IOpCode32BImm
+ {
+ public long Immediate { get; }
+
+ public new static OpCode Create(InstDescriptor inst, ulong address, int opCode) => new OpCodeT32BImm20(inst, address, opCode);
+
+ public OpCodeT32BImm20(InstDescriptor inst, ulong address, int opCode) : base(inst, address, opCode)
+ {
+ uint pc = GetPc();
+
+ int imm11 = (opCode >> 0) & 0x7ff;
+ int j2 = (opCode >> 11) & 1;
+ int j1 = (opCode >> 13) & 1;
+ int imm6 = (opCode >> 16) & 0x3f;
+ int s = (opCode >> 26) & 1;
+
+ int imm32 = imm11 | (imm6 << 11) | (j1 << 17) | (j2 << 18) | (s << 19);
+ imm32 = (imm32 << 13) >> 12;
+
+ Immediate = pc + imm32;
+
+ Cond = (Condition)((opCode >> 22) & 0xf);
+ }
+ }
+} \ No newline at end of file
diff --git a/ARMeilleure/Decoders/OpCodeT32BImm24.cs b/ARMeilleure/Decoders/OpCodeT32BImm24.cs
new file mode 100644
index 00000000..4381be47
--- /dev/null
+++ b/ARMeilleure/Decoders/OpCodeT32BImm24.cs
@@ -0,0 +1,35 @@
+using ARMeilleure.Instructions;
+
+namespace ARMeilleure.Decoders
+{
+ class OpCodeT32BImm24 : OpCodeT32, IOpCode32BImm
+ {
+ public long Immediate { get; }
+
+ public new static OpCode Create(InstDescriptor inst, ulong address, int opCode) => new OpCodeT32BImm24(inst, address, opCode);
+
+ public OpCodeT32BImm24(InstDescriptor inst, ulong address, int opCode) : base(inst, address, opCode)
+ {
+ uint pc = GetPc();
+
+ if (inst.Name == InstName.Blx)
+ {
+ pc &= ~3u;
+ }
+
+ int imm11 = (opCode >> 0) & 0x7ff;
+ int j2 = (opCode >> 11) & 1;
+ int j1 = (opCode >> 13) & 1;
+ int imm10 = (opCode >> 16) & 0x3ff;
+ int s = (opCode >> 26) & 1;
+
+ int i1 = j1 ^ s ^ 1;
+ int i2 = j2 ^ s ^ 1;
+
+ int imm32 = imm11 | (imm10 << 11) | (i2 << 21) | (i1 << 22) | (s << 23);
+ imm32 = (imm32 << 9) >> 8;
+
+ Immediate = pc + imm32;
+ }
+ }
+} \ No newline at end of file
diff --git a/ARMeilleure/Decoders/OpCodeTable.cs b/ARMeilleure/Decoders/OpCodeTable.cs
index d290e554..ad696104 100644
--- a/ARMeilleure/Decoders/OpCodeTable.cs
+++ b/ARMeilleure/Decoders/OpCodeTable.cs
@@ -1050,7 +1050,11 @@ namespace ARMeilleure.Decoders
SetT32("11101011010xxxxx0xxxxxxxxxxxxxxx", InstName.Adc, InstEmit32.Adc, OpCodeT32AluRsImm.Create);
SetT32("11101011000<xxxx0xxx<<<<xxxxxxxx", InstName.Add, InstEmit32.Add, OpCodeT32AluRsImm.Create);
SetT32("11101010000<xxxx0xxx<<<<xxxxxxxx", InstName.And, InstEmit32.And, OpCodeT32AluRsImm.Create);
+ SetT32("11110x<<<xxxxxxx10x0xxxxxxxxxxxx", InstName.B, InstEmit32.B, OpCodeT32BImm20.Create);
+ SetT32("11110xxxxxxxxxxx10x1xxxxxxxxxxxx", InstName.B, InstEmit32.B, OpCodeT32BImm24.Create);
SetT32("11101010001xxxxx0xxxxxxxxxxxxxxx", InstName.Bic, InstEmit32.Bic, OpCodeT32AluRsImm.Create);
+ SetT32("11110xxxxxxxxxxx11x1xxxxxxxxxxxx", InstName.Bl, InstEmit32.Bl, OpCodeT32BImm24.Create);
+ SetT32("11110xxxxxxxxxxx11x0xxxxxxxxxxx0", InstName.Blx, InstEmit32.Blx, OpCodeT32BImm24.Create);
SetT32("111010110001xxxx0xxx1111xxxxxxxx", InstName.Cmn, InstEmit32.Cmn, OpCodeT32AluRsImm.Create);
SetT32("111010111011xxxx0xxx1111xxxxxxxx", InstName.Cmp, InstEmit32.Cmp, OpCodeT32AluRsImm.Create);
SetT32("11101010100<xxxx0xxx<<<<xxxxxxxx", InstName.Eor, InstEmit32.Eor, OpCodeT32AluRsImm.Create);