mirror of
https://github.com/reactos/reactos.git
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bd0a28d1e4
MSVC was previously given a "result" variable to copy the fscale result from st(0). This led to another "fld" FPU stack push at the very end without popping the source value from the FPU stack. Moreover, this copy isn't even needed: A simple "fstp st(1)" at the end pops an element from the FPU stack while effectively storing the result in st(0), the register used for returning a double value. This problem didn't affect GCC, as it is only given the "fscale" instruction and does all necessary stack operations itself. However, looking into the CRT sources, I found many other i386 implementations with inline assembly suffering from the same problem. Fortunately, they have been replaced by pure assembly implementations a while ago, so it's time to finally remove them. ldexp would have also been a candidate for a pure assembly implementation, but the required check for NaN and setting errno (verified on Win2003) already outweighs the benefits. And we cannot just do a NaN check with FUCOMI as this is an i686/pentiumpro instruction while we're still targeting i586/pentium. I'm also using this opportunity to clean up the ldexp.c header and only put in the remaining contributors as returned by "git blame". Thanks to NightWolve1975 for reporting the problem! (https://twitter.com/nightwolve1975/status/1099042477531643912) |
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| .. | ||
| conio | ||
| direct | ||
| except | ||
| float | ||
| include | ||
| locale | ||
| math | ||
| mbstring | ||
| mem | ||
| misc | ||
| printf | ||
| process | ||
| search | ||
| setjmp | ||
| signal | ||
| startup | ||
| stdio | ||
| stdlib | ||
| string | ||
| sys_stat | ||
| time | ||
| wine | ||
| wstring | ||
| CMakeLists.txt | ||
| crt.cmake | ||
| libcntpr.cmake | ||
| moldname-msvcrt.def | ||
| msvcrtex.cmake | ||
| oldnames-msvcrt.S | ||
| oldnames.cmake | ||
| precomp.h | ||
| README.txt | ||
Big chunks of this CRT library are taken from Wine's msvcrt implementation, you can find a list of synced files in README.WINE file. Notes: 1. When syncing, omit MSVCRT_ prefix where possible, Wine has to keep this because they are linking with *both* original crt, and ms crt implementation. ReactOS has the only CRT, so no need to make distinct functions. 2. ReactOS compiles two versions of the CRT library, one for usermode (called just "crt"), and one version for kernelmode usage (called "libcntpr"). In order to separate the code, you can use #ifdef _LIBCNT_ for libcntpr code.