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Implement BX

This commit is contained in:
Jeffrey Pfau 2013-04-11 00:14:12 -07:00
parent a511df7920
commit d278429b43
3 changed files with 20 additions and 6 deletions
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4
src/arm.c
View File

@ -1,6 +1,8 @@
#include "arm.h"
#include "isa-arm.h"
#include "isa-inlines.h"
#include "isa-thumb.h"
static inline enum RegisterBank _ARMSelectBank(enum PrivilegeMode);
@ -107,7 +109,7 @@ void ARMReset(struct ARMCore* cpu) {
}
void ARMRun(struct ARMCore* cpu) {
if (cpu->executionMode) {
if (cpu->executionMode == MODE_THUMB) {
ThumbStep(cpu);
} else {
ARMStep(cpu);

14
src/isa-arm.c
View File

@ -126,10 +126,6 @@ void ARMStep(struct ARMCore* cpu) {
// Instruction definitions
// Beware pre-processor antics
#define ARM_WRITE_PC \
cpu->gprs[ARM_PC] = (cpu->gprs[ARM_PC] & -WORD_SIZE_ARM) + WORD_SIZE_ARM; \
cpu->memory->setActiveRegion(cpu->memory, cpu->gprs[ARM_PC]);
#define ARM_ADDITION_S(M, N, D) \
if (rd == ARM_PC && _ARMModeHasSPSR(cpu->cpsr.priv)) { \
cpu->cpsr = cpu->spsr; \
@ -412,7 +408,15 @@ DEFINE_INSTRUCTION_ARM(B, \
ARM_WRITE_PC;)
DEFINE_INSTRUCTION_ARM(BL, ARM_STUB)
DEFINE_INSTRUCTION_ARM(BX, ARM_STUB)
DEFINE_INSTRUCTION_ARM(BX, \
int rm = opcode & 0x0000000F; \
_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

8
src/isa-inlines.h
View File

@ -54,6 +54,14 @@
#define ARM_STUB cpu->board->hitStub(cpu->board, opcode)
#define ARM_WRITE_PC \
cpu->gprs[ARM_PC] = (cpu->gprs[ARM_PC] & -WORD_SIZE_ARM) + WORD_SIZE_ARM; \
cpu->memory->setActiveRegion(cpu->memory, cpu->gprs[ARM_PC]);
#define THUMB_WRITE_PC \
cpu->gprs[ARM_PC] = (cpu->gprs[ARM_PC] & -WORD_SIZE_THUMB) + WORD_SIZE_THUMB; \
cpu->memory->setActiveRegion(cpu->memory, cpu->gprs[ARM_PC]);
static inline int _ARMModeHasSPSR(enum PrivilegeMode mode) {
return mode != MODE_SYSTEM && mode != MODE_USER;
}