diff options
Diffstat (limited to 'erts/configure.in')
| -rw-r--r-- | erts/configure.in | 571 |
1 files changed, 7 insertions, 564 deletions
diff --git a/erts/configure.in b/erts/configure.in index d1c5fe324b..f66445ec25 100644 --- a/erts/configure.in +++ b/erts/configure.in @@ -2701,570 +2701,13 @@ if test X${enable_hipe} = Xyes; then fi AC_SUBST(HIPEBEAMLDFLAGS) -if test X${enable_fp_exceptions} = Xauto ; then - case $host_os in - *linux*) - enable_fp_exceptions=no - AC_MSG_NOTICE([Floating point exceptions disabled by default on Linux]) ;; - darwin*) - enable_fp_exceptions=no - AC_MSG_NOTICE([Floating point exceptions disabled by default on MacOS X]) ;; - *) - ;; - esac -fi - -if test X${enable_fp_exceptions} = Xauto ; then - if test X${enable_hipe} = Xyes; then - enable_fp_exceptions=yes - else - enable_fp_exceptions=no - AC_MSG_NOTICE([Floating point exceptions disabled by default in this configuration]) - fi -fi - -if test X${enable_fp_exceptions} != Xyes ; then - AC_DEFINE(NO_FPE_SIGNALS,[],[Define if floating points exceptions are non-existing/not reliable]) - FPE=unreliable -else - - AC_MSG_CHECKING([for unreliable floating point exceptions]) - - - AC_TRY_RUN([ -/* fpe-test.c */ -#include <stdio.h> -#include <signal.h> -#include <stdlib.h> - -#if defined(__clang__) || defined(__llvm__) -#error "Clang/LLVM generates broken code for FP exceptions" -#endif - -volatile int erl_fp_exception; - -/* - * We expect a single SIGFPE in this test program. - * Getting many more indicates an inadequate SIGFPE handler, - * e.g. using the generic handler on x86. - */ -static void new_fp_exception(void) -{ - if (++erl_fp_exception > 50) { - fprintf(stderr, "SIGFPE loop detected, bailing out\n"); - exit(1); - } -} - -/* Is there no standard identifier for Darwin/MacOSX ? */ -#if defined(__APPLE__) && defined(__MACH__) && !defined(__DARWIN__) -#define __DARWIN__ 1 -#endif - -/* - * Implement unmask_fpe() and check_fpe() based on CPU/OS combination - */ - -#if (defined(__i386__) || defined(__x86_64__)) && defined(__GNUC__) && !defined(__CYGWIN__) && !defined(__MINGW32__) - -static void unmask_x87(void) -{ - unsigned short cw; - __asm__ __volatile__("fstcw %0" : "=m"(cw)); - cw &= ~(0x01|0x04|0x08); /* unmask IM, ZM, OM */ - __asm__ __volatile__("fldcw %0" : : "m"(cw)); -} - -static void unmask_sse2(void) -{ - unsigned int mxcsr; - __asm__ __volatile__("stmxcsr %0" : "=m"(mxcsr)); - mxcsr &= ~(0x003F|0x0680); /* clear exn flags, unmask OM, ZM, IM (not PM, UM, DM) */ - __asm__ __volatile__("ldmxcsr %0" : : "m"(mxcsr)); -} - -#if defined(__x86_64__) - -static inline int cpu_has_sse2(void) { return 1; } - -#else /* !__x86_64__ */ - -/* - * Check if an x86-32 processor has SSE2. - */ -static unsigned int xor_eflags(unsigned int mask) -{ - unsigned int eax, edx; - - eax = mask; /* eax = mask */ - __asm__("pushfl\n\t" - "popl %0\n\t" /* edx = original EFLAGS */ - "xorl %0, %1\n\t" /* eax = mask ^ EFLAGS */ - "pushl %1\n\t" - "popfl\n\t" /* new EFLAGS = mask ^ original EFLAGS */ - "pushfl\n\t" - "popl %1\n\t" /* eax = new EFLAGS */ - "xorl %0, %1\n\t" /* eax = new EFLAGS ^ old EFLAGS */ - "pushl %0\n\t" - "popfl" /* restore original EFLAGS */ - : "=d"(edx), "=a"(eax) - : "1"(eax)); - return eax; -} - -static __inline__ unsigned int cpuid_eax(unsigned int op) -{ - unsigned int eax, save_ebx; - - /* In PIC mode i386 reserves EBX. So we must save - and restore it ourselves to not upset gcc. */ - __asm__( - "movl %%ebx, %1\n\t" - "cpuid\n\t" - "movl %1, %%ebx" - : "=a"(eax), "=m"(save_ebx) - : "0"(op) - : "cx", "dx"); - return eax; -} - -static __inline__ unsigned int cpuid_edx(unsigned int op) -{ - unsigned int eax, edx, save_ebx; - - /* In PIC mode i386 reserves EBX. So we must save - and restore it ourselves to not upset gcc. */ - __asm__( - "movl %%ebx, %2\n\t" - "cpuid\n\t" - "movl %2, %%ebx" - : "=a"(eax), "=d"(edx), "=m"(save_ebx) - : "0"(op) - : "cx"); - return edx; -} - -/* The AC bit, bit #18, is a new bit introduced in the EFLAGS - * register on the Intel486 processor to generate alignment - * faults. This bit cannot be set on the Intel386 processor. - */ -static __inline__ int is_386(void) -{ - return ((xor_eflags(1<<18) >> 18) & 1) == 0; -} - -/* Newer x86 processors have a CPUID instruction, as indicated by - * the ID bit (#21) in EFLAGS being modifiable. - */ -static __inline__ int has_CPUID(void) -{ - return (xor_eflags(1<<21) >> 21) & 1; -} - -static int cpu_has_sse2(void) -{ - unsigned int maxlev, features; - static int has_sse2 = -1; - - if (has_sse2 >= 0) - return has_sse2; - has_sse2 = 0; - - if (is_386()) - return 0; - if (!has_CPUID()) - return 0; - maxlev = cpuid_eax(0); - /* Intel A-step Pentium had a preliminary version of CPUID. - It also didn't have SSE2. */ - if ((maxlev & 0xFFFFFF00) == 0x0500) - return 0; - /* If max level is zero then CPUID cannot report any features. */ - if (maxlev == 0) - return 0; - features = cpuid_edx(1); - has_sse2 = (features & (1 << 26)) != 0; - - return has_sse2; -} -#endif /* !__x86_64__ */ - -static void unmask_fpe(void) -{ - unmask_x87(); - if (cpu_has_sse2()) - unmask_sse2(); -} - -static __inline__ int check_fpe(double f) -{ - __asm__ __volatile__("fwait" : "=m"(erl_fp_exception) : "m"(f)); - if (!erl_fp_exception) - return 0; - __asm__ __volatile__("fninit"); - unmask_fpe(); - return 1; -} - -#elif defined(__sparc__) && defined(__linux__) - -#if defined(__arch64__) -#define LDX "ldx" -#define STX "stx" -#else -#define LDX "ld" -#define STX "st" -#endif - -static void unmask_fpe(void) -{ - unsigned long fsr; - - __asm__(STX " %%fsr, %0" : "=m"(fsr)); - fsr &= ~(0x1FUL << 23); /* clear FSR[TEM] field */ - fsr |= (0x1AUL << 23); /* enable NV, OF, DZ exceptions */ - __asm__ __volatile__(LDX " %0, %%fsr" : : "m"(fsr)); -} - -static __inline__ int check_fpe(double f) -{ - __asm__ __volatile__("" : "=m"(erl_fp_exception) : "em"(f)); - return erl_fp_exception; -} - -#elif (defined(__powerpc__) && defined(__linux__)) || (defined(__ppc__) && defined(__DARWIN__)) - -#if defined(__linux__) - -#include <sys/prctl.h> - -static void set_fpexc_precise(void) -{ - if (prctl(PR_SET_FPEXC, PR_FP_EXC_PRECISE) < 0) { - perror("PR_SET_FPEXC"); - exit(1); - } -} - -#elif defined(__DARWIN__) - -#include <mach/mach.h> -#include <pthread.h> - -/* - * FE0 FE1 MSR bits - * 0 0 floating-point exceptions disabled - * 0 1 floating-point imprecise nonrecoverable - * 1 0 floating-point imprecise recoverable - * 1 1 floating-point precise mode - * - * Apparently: - * - Darwin 5.5 (MacOS X <= 10.1) starts with FE0 == FE1 == 0, - * and resets FE0 and FE1 to 0 after each SIGFPE. - * - Darwin 6.0 (MacOS X 10.2) starts with FE0 == FE1 == 1, - * and does not reset FE0 or FE1 after a SIGFPE. - */ -#define FE0_MASK (1<<11) -#define FE1_MASK (1<<8) - -/* a thread cannot get or set its own MSR bits */ -static void *fpu_fpe_enable(void *arg) -{ - thread_t t = *(thread_t*)arg; - struct ppc_thread_state state; - unsigned int state_size = PPC_THREAD_STATE_COUNT; - - if (thread_get_state(t, PPC_THREAD_STATE, (natural_t*)&state, &state_size) != KERN_SUCCESS) { - perror("thread_get_state"); - exit(1); - } - if ((state.srr1 & (FE1_MASK|FE0_MASK)) != (FE1_MASK|FE0_MASK)) { -#if 0 - /* This would also have to be performed in the SIGFPE handler - to work around the MSR reset older Darwin releases do. */ - state.srr1 |= (FE1_MASK|FE0_MASK); - thread_set_state(t, PPC_THREAD_STATE, (natural_t*)&state, state_size); -#else - fprintf(stderr, "srr1 == 0x%08x, your Darwin is too old\n", state.srr1); - exit(1); -#endif - } - return NULL; /* Ok, we appear to be on Darwin 6.0 or later */ -} - -static void set_fpexc_precise(void) -{ - thread_t self = mach_thread_self(); - pthread_t enabler; - - if (pthread_create(&enabler, NULL, fpu_fpe_enable, &self)) { - perror("pthread_create"); - } else if (pthread_join(enabler, NULL)) { - perror("pthread_join"); - } -} - -#endif - -static void set_fpscr(unsigned int fpscr) -{ - union { - double d; - unsigned int fpscr[2]; - } u; - u.fpscr[0] = 0xFFF80000; - u.fpscr[1] = fpscr; - __asm__ __volatile__("mtfsf 255,%0" : : "f"(u.d)); -} - -static void unmask_fpe(void) -{ - set_fpexc_precise(); - set_fpscr(0x80|0x40|0x10); /* VE, OE, ZE; not UE or XE */ -} - -static __inline__ int check_fpe(double f) -{ - __asm__ __volatile__("" : "=m"(erl_fp_exception) : "fm"(f)); - return erl_fp_exception; -} - -#else - -#include <ieeefp.h> - -#define unmask_fpe() fpsetmask(FP_X_INV | FP_X_OFL | FP_X_DZ) - -static __inline__ int check_fpe(double f) -{ - __asm__ __volatile__("" : "=m"(erl_fp_exception) : "g"(f)); - return erl_fp_exception; -} - -#endif - -/* - * Implement SIGFPE handler based on CPU/OS combination - */ - -#if (defined(__linux__) && (defined(__i386__) || defined(__x86_64__) || defined(__sparc__) || defined(__powerpc__))) || (defined(__DARWIN__) && (defined(__i386__) || defined(__x86_64__) || defined(__ppc__))) || (defined(__FreeBSD__) && (defined(__i386__) || defined(__x86_64__))) || ((defined(__OpenBSD__) || defined(__NetBSD__)) && defined(__x86_64__)) || (defined(__sun__) && defined(__x86_64__)) - -#if defined(__linux__) && defined(__i386__) -#if !defined(X86_FXSR_MAGIC) -#define X86_FXSR_MAGIC 0x0000 -#endif -#elif defined(__FreeBSD__) && defined(__i386__) -#include <sys/types.h> -#include <machine/npx.h> -#elif defined(__FreeBSD__) && defined(__x86_64__) -#include <sys/types.h> -#include <machine/fpu.h> -#elif defined(__DARWIN__) -#include <machine/signal.h> -#elif defined(__OpenBSD__) && defined(__x86_64__) -#include <sys/types.h> -#include <machine/fpu.h> -#endif -#if !(defined(__OpenBSD__) && defined(__x86_64__)) -#include <ucontext.h> -#endif -#include <string.h> - -static void fpe_sig_action(int sig, siginfo_t *si, void *puc) -{ - ucontext_t *uc = puc; -#if defined(__linux__) -#if defined(__x86_64__) - mcontext_t *mc = &uc->uc_mcontext; - fpregset_t fpstate = mc->fpregs; - fpstate->mxcsr = 0x1F80; - fpstate->swd &= ~0xFF; -#elif defined(__i386__) - mcontext_t *mc = &uc->uc_mcontext; - fpregset_t fpstate = mc->fpregs; - if ((fpstate->status >> 16) == X86_FXSR_MAGIC) - ((struct _fpstate*)fpstate)->mxcsr = 0x1F80; - fpstate->sw &= ~0xFF; -#elif defined(__sparc__) && defined(__arch64__) - /* on SPARC the 3rd parameter points to a sigcontext not a ucontext */ - struct sigcontext *sc = (struct sigcontext*)puc; - sc->sigc_regs.tpc = sc->sigc_regs.tnpc; - sc->sigc_regs.tnpc += 4; -#elif defined(__sparc__) - /* on SPARC the 3rd parameter points to a sigcontext not a ucontext */ - struct sigcontext *sc = (struct sigcontext*)puc; - sc->si_regs.pc = sc->si_regs.npc; - sc->si_regs.npc = (unsigned long)sc->si_regs.npc + 4; -#elif defined(__powerpc__) -#if defined(__powerpc64__) - mcontext_t *mc = &uc->uc_mcontext; - unsigned long *regs = &mc->gp_regs[0]; -#else - mcontext_t *mc = uc->uc_mcontext.uc_regs; - unsigned long *regs = &mc->gregs[0]; -#endif - regs[PT_NIP] += 4; - regs[PT_FPSCR] = 0x80|0x40|0x10; /* VE, OE, ZE; not UE or XE */ -#endif -#elif defined(__DARWIN__) -#if defined(DARWIN_MODERN_MCONTEXT) -#if defined(__x86_64__) - mcontext_t mc = uc->uc_mcontext; - struct __darwin_x86_float_state64 *fpstate = &mc->__fs; - fpstate->__fpu_mxcsr = 0x1F80; - *(unsigned short *)&fpstate->__fpu_fsw &= ~0xFF; -#elif defined(__i386__) - mcontext_t mc = uc->uc_mcontext; - struct __darwin_i386_float_state *fpstate = &mc->__fs; - fpstate->__fpu_mxcsr = 0x1F80; - *(unsigned short *)&fpstate->__fpu_fsw &= ~0xFF; -#elif defined(__ppc__) - mcontext_t mc = uc->uc_mcontext; - mc->ss.srr0 += 4; - mc->fs.fpscr = 0x80|0x40|0x10; -#endif -#else -#if defined(__x86_64__) - mcontext_t mc = uc->uc_mcontext; - struct x86_float_state64_t *fpstate = &mc->fs; - fpstate->fpu_mxcsr = 0x1F80; - *(unsigned short *)&fpstate->fpu_fsw &= ~0xFF; -#elif defined(__i386__) - mcontext_t mc = uc->uc_mcontext; - x86_float_state32_t *fpstate = &mc->fs; - fpstate->fpu_mxcsr = 0x1F80; - *(unsigned short *)&fpstate->fpu_fsw &= ~0xFF; -#elif defined(__ppc__) - mcontext_t mc = uc->uc_mcontext; - mc->ss.srr0 += 4; - mc->fs.fpscr = 0x80|0x40|0x10; -#endif -#endif -#elif defined(__FreeBSD__) && defined(__x86_64__) - mcontext_t *mc = &uc->uc_mcontext; - struct savefpu *savefpu = (struct savefpu*)&mc->mc_fpstate; - struct envxmm *envxmm = &savefpu->sv_env; - envxmm->en_mxcsr = 0x1F80; - envxmm->en_sw &= ~0xFF; -#elif defined(__FreeBSD__) && defined(__i386__) - mcontext_t *mc = &uc->uc_mcontext; - union savefpu *savefpu = (union savefpu*)&mc->mc_fpstate; - if (mc->mc_fpformat == _MC_FPFMT_XMM) { - struct envxmm *envxmm = &savefpu->sv_xmm.sv_env; - envxmm->en_mxcsr = 0x1F80; - envxmm->en_sw &= ~0xFF; - } else { - struct env87 *env87 = &savefpu->sv_87.sv_env; - env87->en_sw &= ~0xFF; - } -#elif defined(__OpenBSD__) && defined(__x86_64__) - struct fxsave64 *fxsave = uc->sc_fpstate; - fxsave->fx_mxcsr = 0x1F80; - fxsave->fx_fsw &= ~0xFF; -#elif defined(__NetBSD__) && defined(__x86_64__) - mcontext_t *mc = &uc->uc_mcontext; - struct fxsave64 *fxsave = (struct fxsave64 *)&mc->__fpregs; - fxsave->fx_mxcsr = 0x1F80; - fxsave->fx_fsw &= ~0xFF; -#elif defined(__sun__) && defined(__x86_64__) - mcontext_t *mc = &uc->uc_mcontext; - struct fpchip_state *fpstate = &mc->fpregs.fp_reg_set.fpchip_state; - fpstate->mxcsr = 0x1F80; - fpstate->sw &= ~0xFF; -#endif - new_fp_exception(); -} - -static void catch_sigfpe(void) -{ - struct sigaction act; - - memset(&act, 0, sizeof act); - act.sa_sigaction = fpe_sig_action; - act.sa_flags = SA_SIGINFO; - sigaction(SIGFPE, &act, NULL); -} - -#else - -static void fpe_sig_handler(int sig) -{ - new_fp_exception(); -} - -static void catch_sigfpe(void) -{ - signal(SIGFPE, fpe_sig_handler); -} - -#endif - -/* - * Generic test code - */ - -static void do_init(void) -{ - catch_sigfpe(); - unmask_fpe(); -} - -double a = 3.23e133; -double b = 3.57e257; -double res; - -void do_fmul(void) -{ - res = a * b; -} - -int do_check(void) -{ - if (check_fpe(res)) { - fprintf(stderr, "res = %g, FPE worked\n", res); - return 0; - } else { - fprintf(stderr, "res = %g, FPE failed\n", res); - return 1; - } -} - -int main(int argc, const char **argv) -{ - if (argc == 3) { - a = atof(argv[1]); - b = atof(argv[2]); - } - do_init(); - do_fmul(); - return do_check(); -} -], -erl_ok=yes, -erl_ok=no, -[ -case X$erl_xcomp_reliable_fpe in - X) erl_ok=cross;; - Xyes|Xno) erl_ok=$erl_xcomp_reliable_fpe;; - *) AC_MSG_ERROR([Bad erl_xcomp_reliable_fpe value: $erl_xcomp_reliable_fpe]);; -esac -]) - - if test $erl_ok = yes; then - FPE=reliable - AC_MSG_RESULT(reliable) - else - FPE=unreliable - AC_MSG_RESULT([unreliable; testing in software instead]) - AC_DEFINE(NO_FPE_SIGNALS,[],[Define if floating points exceptions are non-existing/not reliable]) - if test $erl_ok = cross; then - AC_MSG_WARN([result unreliable guessed because of cross compilation]) - fi - fi -fi - -AC_SUBST(FPE) - +dnl Permanently disable floating point exceptions. +dnl On x86/amd64, floating points exceptions have +dnl unresolved stability issues. +AC_MSG_CHECKING([for unreliable floating point exceptions]) +FPE=unreliable +AC_MSG_RESULT([unreliable]) +AC_DEFINE(NO_FPE_SIGNALS,[],[Define if floating points exceptions are non-existing/not reliable]) dnl dnl Some operating systems allow you to redefine FD_SETSIZE to be able |