From: Myah Caron Subject: [PATCH] msvcrt: Don't set MXCSR in _control87. Message-Id: Date: Thu, 02 Jul 2020 21:57:02 +0000 Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=27594 Signed-off-by: Myah Caron --- This appears to match native MSVCRT's behavior, at least the one provided by vcrun6. I'm not sure if the style is correct (the helper being directly below the __control87_2 comment). --- dlls/msvcrt/math.c | 61 +++++++++++++++++++++++++++++----------------- 1 file changed, 38 insertions(+), 23 deletions(-) diff --git a/dlls/msvcrt/math.c b/dlls/msvcrt/math.c index eae917076f..7ad79a07e5 100644 --- a/dlls/msvcrt/math.c +++ b/dlls/msvcrt/math.c @@ -1101,6 +1101,41 @@ double CDECL MSVCRT__chgsign(double num) * Not exported by native msvcrt, added in msvcr80. */ #ifdef __i386__ +static unsigned int get_flags_from_mxcsr(void) { +#ifdef __GNUC__ + unsigned long fpword; + unsigned int flags; + + __asm__ __volatile__( "stmxcsr %0" : "=m" (fpword) ); + + /* Convert into mask constants */ + flags = 0; + if (fpword & 0x80) flags |= MSVCRT__EM_INVALID; + if (fpword & 0x100) flags |= MSVCRT__EM_DENORMAL; + if (fpword & 0x200) flags |= MSVCRT__EM_ZERODIVIDE; + if (fpword & 0x400) flags |= MSVCRT__EM_OVERFLOW; + if (fpword & 0x800) flags |= MSVCRT__EM_UNDERFLOW; + if (fpword & 0x1000) flags |= MSVCRT__EM_INEXACT; + switch (fpword & 0x6000) + { + case 0x6000: flags |= MSVCRT__RC_UP|MSVCRT__RC_DOWN; break; + case 0x4000: flags |= MSVCRT__RC_UP; break; + case 0x2000: flags |= MSVCRT__RC_DOWN; break; + } + switch (fpword & 0x8040) + { + case 0x0040: flags |= MSVCRT__DN_FLUSH_OPERANDS_SAVE_RESULTS; break; + case 0x8000: flags |= MSVCRT__DN_SAVE_OPERANDS_FLUSH_RESULTS; break; + case 0x8040: flags |= MSVCRT__DN_FLUSH; break; + } + + return flags; +#else + FIXME( "not implemented\n" ); + return 0; +#endif +} + int CDECL __control87_2( unsigned int newval, unsigned int mask, unsigned int *x86_cw, unsigned int *sse2_cw ) { @@ -1170,28 +1205,7 @@ int CDECL __control87_2( unsigned int newval, unsigned int mask, if (sse2_supported) { - __asm__ __volatile__( "stmxcsr %0" : "=m" (fpword) ); - - /* Convert into mask constants */ - flags = 0; - if (fpword & 0x80) flags |= MSVCRT__EM_INVALID; - if (fpword & 0x100) flags |= MSVCRT__EM_DENORMAL; - if (fpword & 0x200) flags |= MSVCRT__EM_ZERODIVIDE; - if (fpword & 0x400) flags |= MSVCRT__EM_OVERFLOW; - if (fpword & 0x800) flags |= MSVCRT__EM_UNDERFLOW; - if (fpword & 0x1000) flags |= MSVCRT__EM_INEXACT; - switch (fpword & 0x6000) - { - case 0x6000: flags |= MSVCRT__RC_UP|MSVCRT__RC_DOWN; break; - case 0x4000: flags |= MSVCRT__RC_UP; break; - case 0x2000: flags |= MSVCRT__RC_DOWN; break; - } - switch (fpword & 0x8040) - { - case 0x0040: flags |= MSVCRT__DN_FLUSH_OPERANDS_SAVE_RESULTS; break; - case 0x8000: flags |= MSVCRT__DN_SAVE_OPERANDS_FLUSH_RESULTS; break; - case 0x8040: flags |= MSVCRT__DN_FLUSH; break; - } + flags = get_flags_from_mxcsr(); TRACE( "sse2 flags=%08x newval=%08x mask=%08x\n", flags, newval, mask ); if (mask) @@ -1241,7 +1255,8 @@ unsigned int CDECL _control87(unsigned int newval, unsigned int mask) #ifdef __i386__ unsigned int sse2_cw; - __control87_2( newval, mask, &flags, &sse2_cw ); + __control87_2( newval, mask, &flags, 0 ); + sse2_cw = get_flags_from_mxcsr(); if ((flags ^ sse2_cw) & (MSVCRT__MCW_EM | MSVCRT__MCW_RC)) flags |= MSVCRT__EM_AMBIGUOUS; #elif defined(__x86_64__) -- 2.26.2