all repos — mgba @ 89936d1b94e1e95ebf18b8d4737f7e2124596b9a

mGBA Game Boy Advance Emulator

ARM9: Implement BLX (2)
Jeffrey Pfau jeffrey@endrift.com
Mon, 06 Jun 2016 00:28:27 -0700
commit

89936d1b94e1e95ebf18b8d4737f7e2124596b9a

parent

3796c32eb467928cdf12bf95c010d2319b841268

5 files changed, 19 insertions(+), 1 deletions(-)

jump to
M src/arm/decoder-arm.c → src/arm/decoder-arm.c 
@@ -351,6 +351,11 @@ info->op1.reg = opcode & 0x0000000F;
 	info->operandFormat = ARM_OPERAND_REGISTER_1;
 	info->branchType = ARM_BRANCH_INDIRECT;)
 
+DEFINE_DECODER_ARM(BLX2, BLX,
+	info->op1.reg = opcode & 0x0000000F;
+	info->operandFormat = ARM_OPERAND_REGISTER_1;
+	info->branchType = ARM_BRANCH_LINKED | ARM_BRANCH_INDIRECT;)
+
 // End branch definitions
 
 // Begin coprocessor definitions
M src/arm/decoder.c → src/arm/decoder.c 
@@ -250,6 +250,7 @@ "b",
 	"bic",
 	"bkpt",
 	"bl",
+	"blx",
 	"bx",
 	"cdp",
 	"clz",
M src/arm/decoder.h → src/arm/decoder.h 
@@ -158,6 +158,7 @@ ARM_MN_B,
 	ARM_MN_BIC,
 	ARM_MN_BKPT,
 	ARM_MN_BL,
+	ARM_MN_BLX,
 	ARM_MN_BX,
 	ARM_MN_CDP,
 	ARM_MN_CLZ,
M src/arm/emitter-arm.h → src/arm/emitter-arm.h 
@@ -370,7 +370,7 @@ DECLARE_ARM_ALU_BLOCK(EMITTER, TST, ILL, LDRHP, LDRSBP, LDRSHP), \
 	DECLARE_INSTRUCTION_ARM(EMITTER, MSR), \
 	DECLARE_INSTRUCTION_ARM(EMITTER, BX), \
 	DECLARE_INSTRUCTION_ARM(EMITTER, ILL), \
-	DECLARE_INSTRUCTION_ARM(EMITTER, ILL), \
+	DECLARE_INSTRUCTION_ARM(EMITTER, BLX2), \
 	DECLARE_INSTRUCTION_ARM(EMITTER, ILL), \
 	DECLARE_INSTRUCTION_ARM(EMITTER, ILL), \
 	DECLARE_INSTRUCTION_ARM(EMITTER, ILL), \
M src/arm/isa-arm.c → src/arm/isa-arm.c 
@@ -613,6 +613,17 @@ if (cpu->executionMode == MODE_THUMB) {
 		THUMB_WRITE_PC;
 	} else {
 		ARM_WRITE_PC;
+
+	})
+DEFINE_INSTRUCTION_ARM(BLX2,
+	int rm = opcode & 0x0000000F;
+	cpu->gprs[ARM_LR] = cpu->gprs[ARM_PC] - WORD_SIZE_ARM;
+	_ARMSetMode(cpu, cpu->gprs[rm] & 0x00000001);
+	cpu->gprs[ARM_PC] = cpu->gprs[rm] & 0xFFFFFFFE;
+	if (cpu->executionMode == MODE_THUMB) {
+		THUMB_WRITE_PC;
+	} else {
+		ARM_WRITE_PC;
 	})
 
 // End branch definitions