all repos — mgba @ 5dca78356932bc4e89ff55856eeda25e42e8e8db

mGBA Game Boy Advance Emulator

ARM9: Fix blx lr
Vicki Pfau vi@endrift.com
Fri, 17 Mar 2017 13:06:11 -0700
commit

5dca78356932bc4e89ff55856eeda25e42e8e8db

parent

92e4c859a715221981ffd270a1b7ffaeabe4a639

2 files changed, 7 insertions(+), 5 deletions(-)

jump to
M src/arm/isa-arm.c → src/arm/isa-arm.c 
@@ -706,9 +706,10 @@ THUMB_WRITE_PC;)
 
 DEFINE_INSTRUCTION_ARM(BLX2,
 	int rm = opcode & 0x0000000F;
+	int address = cpu->gprs[rm];
 	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;
+	_ARMSetMode(cpu, address & 0x00000001);
+	cpu->gprs[ARM_PC] = address & 0xFFFFFFFE;
 	if (cpu->executionMode == MODE_THUMB) {
 		THUMB_WRITE_PC;
 	} else {
M src/arm/isa-thumb.c → src/arm/isa-thumb.c 
@@ -422,13 +422,14 @@ })
 
 DEFINE_INSTRUCTION_THUMB(BLX2,
 	int rm = (opcode >> 3) & 0xF;
-	_ARMSetMode(cpu, cpu->gprs[rm] & 0x00000001);
+	int address = cpu->gprs[rm];
+	_ARMSetMode(cpu, address & 0x00000001);
 	int misalign = 0;
 	if (rm == ARM_PC) {
-		misalign = cpu->gprs[rm] & 0x00000002;
+		misalign = address & 0x00000002;
 	}
 	cpu->gprs[ARM_LR] = cpu->gprs[ARM_PC] - 1;
-	cpu->gprs[ARM_PC] = (cpu->gprs[rm] & 0xFFFFFFFE) - misalign;
+	cpu->gprs[ARM_PC] = (address & 0xFFFFFFFE) - misalign;
 	if (cpu->executionMode == MODE_THUMB) {
 		THUMB_WRITE_PC;
 	} else {