diff options
| -rw-r--r-- | target-s390x/cpu.h | 2 | ||||
| -rw-r--r-- | target-s390x/int_helper.c | 51 | ||||
| -rw-r--r-- | target-s390x/misc_helper.c | 20 |
3 files changed, 67 insertions, 6 deletions
diff --git a/target-s390x/cpu.h b/target-s390x/cpu.h index ea1bc86..69269a1 100644 --- a/target-s390x/cpu.h +++ b/target-s390x/cpu.h @@ -931,5 +931,7 @@ uint32_t set_cc_nz_f64(float64 v); /* misc_helper.c */ void program_interrupt(CPUS390XState *env, uint32_t code, int ilen); +void QEMU_NORETURN runtime_exception(CPUS390XState *env, int excp, + uintptr_t retaddr); #endif diff --git a/target-s390x/int_helper.c b/target-s390x/int_helper.c index 80e17f5..839c0e1 100644 --- a/target-s390x/int_helper.c +++ b/target-s390x/int_helper.c @@ -38,22 +38,54 @@ uint64_t HELPER(mul128)(CPUS390XState *env, uint64_t v1, uint64_t v2) } /* 64/32 -> 32 signed division */ -int64_t HELPER(divs32)(CPUS390XState *env, int64_t a, int64_t b) +int64_t HELPER(divs32)(CPUS390XState *env, int64_t a, int64_t b64) { - env->retxl = a % (int32_t)b; - return a / (int32_t)b; + int32_t ret, b = b64; + int64_t q; + + if (b == 0) { + runtime_exception(env, PGM_FIXPT_DIVIDE, GETPC()); + } + + ret = q = a / b; + env->retxl = a % b; + + /* Catch non-representable quotient. */ + if (ret != q) { + runtime_exception(env, PGM_FIXPT_DIVIDE, GETPC()); + } + + return ret; } /* 64/32 -> 32 unsigned division */ -uint64_t HELPER(divu32)(CPUS390XState *env, uint64_t a, uint64_t b) +uint64_t HELPER(divu32)(CPUS390XState *env, uint64_t a, uint64_t b64) { - env->retxl = a % (uint32_t)b; - return a / (uint32_t)b; + uint32_t ret, b = b64; + uint64_t q; + + if (b == 0) { + runtime_exception(env, PGM_FIXPT_DIVIDE, GETPC()); + } + + ret = q = a / b; + env->retxl = a % b; + + /* Catch non-representable quotient. */ + if (ret != q) { + runtime_exception(env, PGM_FIXPT_DIVIDE, GETPC()); + } + + return ret; } /* 64/64 -> 64 signed division */ int64_t HELPER(divs64)(CPUS390XState *env, int64_t a, int64_t b) { + /* Catch divide by zero, and non-representable quotient (MIN / -1). */ + if (b == 0 || (b == -1 && a == (1ll << 63))) { + runtime_exception(env, PGM_FIXPT_DIVIDE, GETPC()); + } env->retxl = a % b; return a / b; } @@ -63,6 +95,10 @@ uint64_t HELPER(divu64)(CPUS390XState *env, uint64_t ah, uint64_t al, uint64_t b) { uint64_t ret; + /* Signal divide by zero. */ + if (b == 0) { + runtime_exception(env, PGM_FIXPT_DIVIDE, GETPC()); + } if (ah == 0) { /* 64 -> 64/64 case */ env->retxl = al % b; @@ -75,6 +111,9 @@ uint64_t HELPER(divu64)(CPUS390XState *env, uint64_t ah, uint64_t al, __uint128_t q = a / b; env->retxl = a % b; ret = q; + if (ret != q) { + runtime_exception(env, PGM_FIXPT_DIVIDE, GETPC()); + } #else /* 32-bit hosts would need special wrapper functionality - just abort if we encounter such a case; it's very unlikely anyways. */ diff --git a/target-s390x/misc_helper.c b/target-s390x/misc_helper.c index 2aa1ed0..6dca0eb 100644 --- a/target-s390x/misc_helper.c +++ b/target-s390x/misc_helper.c @@ -41,6 +41,26 @@ #define HELPER_LOG(x...) #endif +/* Raise an exception dynamically from a helper function. */ +void QEMU_NORETURN runtime_exception(CPUS390XState *env, int excp, + uintptr_t retaddr) +{ + int t; + + env->exception_index = EXCP_PGM; + env->int_pgm_code = excp; + + /* Use the (ultimate) callers address to find the insn that trapped. */ + cpu_restore_state(env, retaddr); + + /* Advance past the insn. */ + t = cpu_ldub_code(env, env->psw.addr); + env->int_pgm_ilen = t = get_ilen(t); + env->psw.addr += 2 * t; + + cpu_loop_exit(env); +} + /* Raise an exception statically from a TB. */ void HELPER(exception)(CPUS390XState *env, uint32_t excp) { |