M include/mgba/internal/arm/arm.h → include/mgba/internal/arm/arm.h

@@ -93,6 +93,20 @@ unsigned n : 1;
 #endif
 	};
 
+	struct {
+#if defined(__BIG_ENDIAN__)
+		uint8_t flags;
+		uint8_t status;
+		uint8_t extension;
+		uint8_t control;
+#else
+		uint8_t control;
+		uint8_t extension;
+		uint8_t status;
+		uint8_t flags;
+#endif
+	};
+
 	int32_t packed;
 };
 

M src/arm/isa-arm.c → src/arm/isa-arm.c

@@ -185,6 +185,7 @@ // Instruction definitions
 // Beware pre-processor antics
 
 ATTRIBUTE_NOINLINE static void _additionS(struct ARMCore* cpu, int32_t m, int32_t n, int32_t d) {
+	cpu->cpsr.flags = 0;
 	cpu->cpsr.n = ARM_SIGN(d);
 	cpu->cpsr.z = !d;
 	cpu->cpsr.c = ARM_CARRY_FROM(m, n, d);
@@ -192,6 +193,7 @@ cpu->cpsr.v = ARM_V_ADDITION(m, n, d);
 }
 
 ATTRIBUTE_NOINLINE static void _subtractionS(struct ARMCore* cpu, int32_t m, int32_t n, int32_t d) {
+	cpu->cpsr.flags = 0;
 	cpu->cpsr.n = ARM_SIGN(d);
 	cpu->cpsr.z = !d;
 	cpu->cpsr.c = ARM_BORROW_FROM(m, n, d);

M src/arm/isa-thumb.c → src/arm/isa-thumb.c

@@ -12,12 +12,14 @@ // Instruction definitions
 // Beware pre-processor insanity
 
 #define THUMB_ADDITION_S(M, N, D) \
+	cpu->cpsr.flags = 0; \
 	cpu->cpsr.n = ARM_SIGN(D); \
 	cpu->cpsr.z = !(D); \
 	cpu->cpsr.c = ARM_CARRY_FROM(M, N, D); \
 	cpu->cpsr.v = ARM_V_ADDITION(M, N, D);
 
 #define THUMB_SUBTRACTION_S(M, N, D) \
+	cpu->cpsr.flags = 0; \
 	cpu->cpsr.n = ARM_SIGN(D); \
 	cpu->cpsr.z = !(D); \
 	cpu->cpsr.c = ARM_BORROW_FROM(M, N, D); \