diff --git a/include/mgba/internal/arm/emitter-inlines.h b/include/mgba/internal/arm/emitter-inlines.h
index 38bab70bd..ba4fb9951 100644
--- a/include/mgba/internal/arm/emitter-inlines.h
+++ b/include/mgba/internal/arm/emitter-inlines.h
@@ -29,4 +29,6 @@
LEFT, \
RIGHT
+#define MIN_V(PASS, FAIL, COND) (COND ? PASS : FAIL)
+
#endif
diff --git a/include/mgba/internal/arm/emitter-thumb.h b/include/mgba/internal/arm/emitter-thumb.h
index 7d27524b2..f2e69d0bb 100644
--- a/include/mgba/internal/arm/emitter-thumb.h
+++ b/include/mgba/internal/arm/emitter-thumb.h
@@ -17,7 +17,7 @@
DECLARE_INSTRUCTION_THUMB(EMITTER, NAME ## 10), \
DECLARE_INSTRUCTION_THUMB(EMITTER, NAME ## 11)
-#define DECLARE_THUMB_EMITTER_BLOCK(EMITTER) \
+#define DECLARE_THUMB_EMITTER_BLOCK(EMITTER, V) \
DO_8(DO_4(DECLARE_INSTRUCTION_THUMB(EMITTER, LSL1))), \
DO_8(DO_4(DECLARE_INSTRUCTION_THUMB(EMITTER, LSR1))), \
DO_8(DO_4(DECLARE_INSTRUCTION_THUMB(EMITTER, ASR1))), \
@@ -106,7 +106,7 @@
DO_4(DECLARE_INSTRUCTION_THUMB(EMITTER, ILL)), \
DO_4(DECLARE_INSTRUCTION_THUMB(EMITTER, SWI)), \
DO_8(DO_4(DECLARE_INSTRUCTION_THUMB(EMITTER, B))), \
- DO_8(DO_4(DECLARE_INSTRUCTION_THUMB(EMITTER, ILL))), \
+ DO_8(DO_4(MIN_V(DECLARE_INSTRUCTION_THUMB(EMITTER, BLX1), DECLARE_INSTRUCTION_THUMB(EMITTER, ILL), V >= 5))), \
DO_8(DO_4(DECLARE_INSTRUCTION_THUMB(EMITTER, BL1))), \
DO_8(DO_4(DECLARE_INSTRUCTION_THUMB(EMITTER, BL2))) \
diff --git a/include/mgba/internal/arm/isa-thumb.h b/include/mgba/internal/arm/isa-thumb.h
index 330a4faf8..c85636bb2 100644
--- a/include/mgba/internal/arm/isa-thumb.h
+++ b/include/mgba/internal/arm/isa-thumb.h
@@ -13,7 +13,8 @@ CXX_GUARD_START
struct ARMCore;
typedef void (*ThumbInstruction)(struct ARMCore*, uint16_t opcode);
-extern const ThumbInstruction _thumbTable[0x400];
+extern const ThumbInstruction _thumbv4Table[0x400];
+extern const ThumbInstruction _thumbv5Table[0x400];
CXX_GUARD_END
diff --git a/src/arm/arm.c b/src/arm/arm.c
index dc6714681..7db39d7a9 100644
--- a/src/arm/arm.c
+++ b/src/arm/arm.c
@@ -223,15 +223,6 @@ void ARMRaiseUndefined(struct ARMCore* cpu) {
cpu->cycles += currentCycles;
}
-static inline void ThumbStep(struct ARMCore* cpu) {
- uint32_t opcode = cpu->prefetch[0];
- cpu->prefetch[0] = cpu->prefetch[1];
- cpu->gprs[ARM_PC] += WORD_SIZE_THUMB;
- LOAD_16(cpu->prefetch[1], cpu->gprs[ARM_PC] & cpu->memory.activeMask, cpu->memory.activeRegion);
- ThumbInstruction instruction = _thumbTable[opcode >> 6];
- instruction(cpu, opcode);
-}
-
#define ARM_IMPLEMENT(VERSION) \
static inline void ARM ## VERSION ## Step(struct ARMCore* cpu) { \
uint32_t opcode = cpu->prefetch[0]; \
@@ -297,9 +288,18 @@ static inline void ThumbStep(struct ARMCore* cpu) {
instruction(cpu, opcode); \
} \
\
- void ARM ## VERSION ## Run(struct ARMCore* cpu) { \
+ static inline void Thumb ## VERSION ## Step(struct ARMCore* cpu) { \
+ uint32_t opcode = cpu->prefetch[0]; \
+ cpu->prefetch[0] = cpu->prefetch[1]; \
+ cpu->gprs[ARM_PC] += WORD_SIZE_THUMB; \
+ LOAD_16(cpu->prefetch[1], cpu->gprs[ARM_PC] & cpu->memory.activeMask, cpu->memory.activeRegion); \
+ ThumbInstruction instruction = _thumb ## VERSION ## Table[opcode >> 6]; \
+ instruction(cpu, opcode); \
+ } \
+ \
+ void ARM ## VERSION ## Run(struct ARMCore* cpu) { \
if (cpu->executionMode == MODE_THUMB) { \
- ThumbStep(cpu); \
+ Thumb ## VERSION ## Step(cpu); \
} else { \
ARM ## VERSION ## Step(cpu); \
} \
@@ -311,7 +311,7 @@ static inline void ThumbStep(struct ARMCore* cpu) {
void ARM ## VERSION ## RunLoop(struct ARMCore* cpu) { \
if (cpu->executionMode == MODE_THUMB) { \
while (cpu->cycles < cpu->nextEvent) { \
- ThumbStep(cpu); \
+ Thumb ## VERSION ## Step(cpu); \
} \
} else { \
while (cpu->cycles < cpu->nextEvent) { \
@@ -319,28 +319,6 @@ static inline void ThumbStep(struct ARMCore* cpu) {
} \
} \
cpu->irqh.processEvents(cpu); \
- } \
- \
- int32_t ARM ## VERSION ## RunCycles(struct ARMCore* cpu, int32_t cycles) { \
- int32_t startCycles = cpu->cycles; \
- int32_t endCycles = startCycles + cycles; \
- \
- if (cpu->executionMode == MODE_THUMB) { \
- while (cpu->cycles < cpu->nextEvent && cpu->cycles < endCycles) { \
- ThumbStep(cpu); \
- } \
- } else { \
- while (cpu->cycles < cpu->nextEvent && cpu->cycles < endCycles) { \
- ARM ## VERSION ## Step(cpu); \
- } \
- } \
- \
- endCycles = cpu->cycles - startCycles; \
- if (cpu->cycles >= cpu->nextEvent) { \
- /* TODO: Handle HALT */ \
- cpu->irqh.processEvents(cpu); \
- } \
- return endCycles; \
}
ARM_IMPLEMENT(v4)
diff --git a/src/arm/decoder-thumb.c b/src/arm/decoder-thumb.c
index a53da00e9..bb89050a0 100644
--- a/src/arm/decoder-thumb.c
+++ b/src/arm/decoder-thumb.c
@@ -282,6 +282,14 @@ DEFINE_THUMB_DECODER(BL2, BL,
ARM_OPERAND_REGISTER_2 | ARM_OPERAND_IMMEDIATE_3;
info->branchType = ARM_BRANCH_LINKED;)
+DEFINE_THUMB_DECODER(BLX1, BLX,
+ info->op1.reg = ARM_PC;
+ info->op2.reg = ARM_LR;
+ info->op3.immediate = (opcode & 0x07FF) << 1;
+ info->operandFormat = ARM_OPERAND_REGISTER_1 | ARM_OPERAND_AFFECTED_1 |
+ ARM_OPERAND_REGISTER_2 | ARM_OPERAND_IMMEDIATE_3;
+ info->branchType = ARM_BRANCH_LINKED;)
+
DEFINE_THUMB_DECODER(BX, BX,
info->op1.reg = (opcode >> 3) & 0xF;
info->operandFormat = ARM_OPERAND_REGISTER_1;
@@ -295,7 +303,7 @@ DEFINE_THUMB_DECODER(SWI, SWI,
typedef void (*ThumbDecoder)(uint16_t opcode, struct ARMInstructionInfo* info);
static const ThumbDecoder _thumbDecoderTable[0x400] = {
- DECLARE_THUMB_EMITTER_BLOCK(_ThumbDecode)
+ DECLARE_THUMB_EMITTER_BLOCK(_ThumbDecode, 5)
};
void ARMDecodeThumb(uint16_t opcode, struct ARMInstructionInfo* info) {
diff --git a/src/arm/decoder.c b/src/arm/decoder.c
index 32e92f23a..8c7d25540 100644
--- a/src/arm/decoder.c
+++ b/src/arm/decoder.c
@@ -389,6 +389,7 @@ int ARMDisassemble(struct ARMInstructionInfo* info, uint32_t pc, char* buffer, i
break;
case ARM_MN_B:
case ARM_MN_BL:
+ case ARM_MN_BLX:
if (info->operandFormat & ARM_OPERAND_IMMEDIATE_1) {
written = _decodePCRelative(info->op1.immediate, pc, buffer, blen);
ADVANCE(written);
diff --git a/src/arm/isa-thumb.c b/src/arm/isa-thumb.c
index 54faf6ddc..b65483d67 100644
--- a/src/arm/isa-thumb.c
+++ b/src/arm/isa-thumb.c
@@ -382,6 +382,14 @@ DEFINE_INSTRUCTION_THUMB(BL2,
cpu->gprs[ARM_LR] = pc - 1;
THUMB_WRITE_PC;)
+DEFINE_INSTRUCTION_THUMB(BLX1,
+ uint16_t immediate = (opcode & 0x07FF) << 1;
+ uint32_t pc = cpu->gprs[ARM_PC];
+ cpu->gprs[ARM_PC] = (cpu->gprs[ARM_LR] + immediate) & 0xFFFFFFFC;
+ cpu->gprs[ARM_LR] = pc - 1;
+ _ARMSetMode(cpu, MODE_ARM);
+ ARM_WRITE_PC;)
+
DEFINE_INSTRUCTION_THUMB(BX,
int rm = (opcode >> 3) & 0xF;
_ARMSetMode(cpu, cpu->gprs[rm] & 0x00000001);
@@ -398,6 +406,10 @@ DEFINE_INSTRUCTION_THUMB(BX,
DEFINE_INSTRUCTION_THUMB(SWI, cpu->irqh.swi16(cpu, opcode & 0xFF))
-const ThumbInstruction _thumbTable[0x400] = {
- DECLARE_THUMB_EMITTER_BLOCK(_ThumbInstruction)
+const ThumbInstruction _thumbv4Table[0x400] = {
+ DECLARE_THUMB_EMITTER_BLOCK(_ThumbInstruction, 4)
+};
+
+const ThumbInstruction _thumbv5Table[0x400] = {
+ DECLARE_THUMB_EMITTER_BLOCK(_ThumbInstruction, 5)
};