diff options
Diffstat (limited to 'target-xtensa/op_helper.c')
| -rw-r--r-- | target-xtensa/op_helper.c | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/target-xtensa/op_helper.c b/target-xtensa/op_helper.c index 794a834..7c3fb88 100644 --- a/target-xtensa/op_helper.c +++ b/target-xtensa/op_helper.c @@ -100,3 +100,195 @@ uint32_t HELPER(nsau)(uint32_t v) { return v ? clz32(v) : 32; } + +static void copy_window_from_phys(CPUState *env, + uint32_t window, uint32_t phys, uint32_t n) +{ + assert(phys < env->config->nareg); + if (phys + n <= env->config->nareg) { + memcpy(env->regs + window, env->phys_regs + phys, + n * sizeof(uint32_t)); + } else { + uint32_t n1 = env->config->nareg - phys; + memcpy(env->regs + window, env->phys_regs + phys, + n1 * sizeof(uint32_t)); + memcpy(env->regs + window + n1, env->phys_regs, + (n - n1) * sizeof(uint32_t)); + } +} + +static void copy_phys_from_window(CPUState *env, + uint32_t phys, uint32_t window, uint32_t n) +{ + assert(phys < env->config->nareg); + if (phys + n <= env->config->nareg) { + memcpy(env->phys_regs + phys, env->regs + window, + n * sizeof(uint32_t)); + } else { + uint32_t n1 = env->config->nareg - phys; + memcpy(env->phys_regs + phys, env->regs + window, + n1 * sizeof(uint32_t)); + memcpy(env->phys_regs, env->regs + window + n1, + (n - n1) * sizeof(uint32_t)); + } +} + + +static inline unsigned windowbase_bound(unsigned a, const CPUState *env) +{ + return a & (env->config->nareg / 4 - 1); +} + +static inline unsigned windowstart_bit(unsigned a, const CPUState *env) +{ + return 1 << windowbase_bound(a, env); +} + +void xtensa_sync_window_from_phys(CPUState *env) +{ + copy_window_from_phys(env, 0, env->sregs[WINDOW_BASE] * 4, 16); +} + +void xtensa_sync_phys_from_window(CPUState *env) +{ + copy_phys_from_window(env, env->sregs[WINDOW_BASE] * 4, 0, 16); +} + +static void rotate_window_abs(uint32_t position) +{ + xtensa_sync_phys_from_window(env); + env->sregs[WINDOW_BASE] = windowbase_bound(position, env); + xtensa_sync_window_from_phys(env); +} + +static void rotate_window(uint32_t delta) +{ + rotate_window_abs(env->sregs[WINDOW_BASE] + delta); +} + +void HELPER(wsr_windowbase)(uint32_t v) +{ + rotate_window_abs(v); +} + +void HELPER(entry)(uint32_t pc, uint32_t s, uint32_t imm) +{ + int callinc = (env->sregs[PS] & PS_CALLINC) >> PS_CALLINC_SHIFT; + if (s > 3 || ((env->sregs[PS] & (PS_WOE | PS_EXCM)) ^ PS_WOE) != 0) { + qemu_log("Illegal entry instruction(pc = %08x), PS = %08x\n", + pc, env->sregs[PS]); + HELPER(exception_cause)(pc, ILLEGAL_INSTRUCTION_CAUSE); + } else { + env->regs[(callinc << 2) | (s & 3)] = env->regs[s] - (imm << 3); + rotate_window(callinc); + env->sregs[WINDOW_START] |= + windowstart_bit(env->sregs[WINDOW_BASE], env); + } +} + +void HELPER(window_check)(uint32_t pc, uint32_t w) +{ + uint32_t windowbase = windowbase_bound(env->sregs[WINDOW_BASE], env); + uint32_t windowstart = env->sregs[WINDOW_START]; + uint32_t m, n; + + if ((env->sregs[PS] & (PS_WOE | PS_EXCM)) ^ PS_WOE) { + return; + } + + for (n = 1; ; ++n) { + if (n > w) { + return; + } + if (windowstart & windowstart_bit(windowbase + n, env)) { + break; + } + } + + m = windowbase_bound(windowbase + n, env); + rotate_window(n); + env->sregs[PS] = (env->sregs[PS] & ~PS_OWB) | + (windowbase << PS_OWB_SHIFT) | PS_EXCM; + env->sregs[EPC1] = env->pc = pc; + + if (windowstart & windowstart_bit(m + 1, env)) { + HELPER(exception)(EXC_WINDOW_OVERFLOW4); + } else if (windowstart & windowstart_bit(m + 2, env)) { + HELPER(exception)(EXC_WINDOW_OVERFLOW8); + } else { + HELPER(exception)(EXC_WINDOW_OVERFLOW12); + } +} + +uint32_t HELPER(retw)(uint32_t pc) +{ + int n = (env->regs[0] >> 30) & 0x3; + int m = 0; + uint32_t windowbase = windowbase_bound(env->sregs[WINDOW_BASE], env); + uint32_t windowstart = env->sregs[WINDOW_START]; + uint32_t ret_pc = 0; + + if (windowstart & windowstart_bit(windowbase - 1, env)) { + m = 1; + } else if (windowstart & windowstart_bit(windowbase - 2, env)) { + m = 2; + } else if (windowstart & windowstart_bit(windowbase - 3, env)) { + m = 3; + } + + if (n == 0 || (m != 0 && m != n) || + ((env->sregs[PS] & (PS_WOE | PS_EXCM)) ^ PS_WOE) != 0) { + qemu_log("Illegal retw instruction(pc = %08x), " + "PS = %08x, m = %d, n = %d\n", + pc, env->sregs[PS], m, n); + HELPER(exception_cause)(pc, ILLEGAL_INSTRUCTION_CAUSE); + } else { + int owb = windowbase; + + ret_pc = (pc & 0xc0000000) | (env->regs[0] & 0x3fffffff); + + rotate_window(-n); + if (windowstart & windowstart_bit(env->sregs[WINDOW_BASE], env)) { + env->sregs[WINDOW_START] &= ~windowstart_bit(owb, env); + } else { + /* window underflow */ + env->sregs[PS] = (env->sregs[PS] & ~PS_OWB) | + (windowbase << PS_OWB_SHIFT) | PS_EXCM; + env->sregs[EPC1] = env->pc = pc; + + if (n == 1) { + HELPER(exception)(EXC_WINDOW_UNDERFLOW4); + } else if (n == 2) { + HELPER(exception)(EXC_WINDOW_UNDERFLOW8); + } else if (n == 3) { + HELPER(exception)(EXC_WINDOW_UNDERFLOW12); + } + } + } + return ret_pc; +} + +void HELPER(rotw)(uint32_t imm4) +{ + rotate_window(imm4); +} + +void HELPER(restore_owb)(void) +{ + rotate_window_abs((env->sregs[PS] & PS_OWB) >> PS_OWB_SHIFT); +} + +void HELPER(movsp)(uint32_t pc) +{ + if ((env->sregs[WINDOW_START] & + (windowstart_bit(env->sregs[WINDOW_BASE] - 3, env) | + windowstart_bit(env->sregs[WINDOW_BASE] - 2, env) | + windowstart_bit(env->sregs[WINDOW_BASE] - 1, env))) == 0) { + HELPER(exception_cause)(pc, ALLOCA_CAUSE); + } +} + +void HELPER(dump_state)(void) +{ + cpu_dump_state(env, stderr, fprintf, 0); +} |
