TeamHeptaMirrors/gcc
1
0
Fork 1
mirror of https://github.com/gcc-mirror/gcc.git synced 2026-05-06 14:59:39 +02:00
Code Issues Packages Projects Releases Wiki Activity

libgcc: Pass x87 control word in the correct type

Browse Source 
The x87 control word should be passed as an `unsigned short`. Previous
code passed `unsigned int`, and when building with `-masm=intel`,

   __asm__ __volatile__ ("fnstcw\t%0" : "=m" (_cw));

could expand to `fnstcw DWORD PTR [esp+48]` and cause errors like

   {standard input}: Assembler messages:
   {standard input}:7137: Error: operand size mismatch for `fnstcw'

libgcc/ChangeLog:

	PR target/122275
	* config/i386/32/dfp-machine.h (DFP_GET_ROUNDMODE): Change `_frnd_orig` to
	`unsigned short` for x87 control word.
	(DFP_SET_ROUNDMODE): Manipulate the x87 control word as `unsigned short`,
	and manipulate the MXCSR as `unsigned int`.

Signed-off-by: LIU Hao <lh_mouse@126.com>
This commit is contained in:
LIU Hao
2025-10-14 14:46:46 +08:00
committed by Uros Bizjak
parent 1c0897caa5
commit d9b785ab92
1 changed files with 11 additions and 10 deletions
Download Patch File Download Diff File Expand all files Collapse all files

21
libgcc/config/i386/32/dfp-machine.h
View File

@@ -1,7 +1,7 @@
#ifndef _SOFT_FLOAT
/* Get the rounding mode. */
#define DFP_GET_ROUNDMODE \
unsigned int _frnd_orig; \
unsigned short _frnd_orig; \
do \
{ \
__asm__ __volatile__ ("fnstcw\t%0" : "=m" (_frnd_orig)); \
@@ -13,17 +13,18 @@
#define DFP_SET_ROUNDMODE(round) \
do \
{ \
unsigned int _cw; \
__asm__ __volatile__ ("fnstcw\t%0" : "=m" (_cw)); \
_cw &= ~FP_RND_MASK; \
_cw |= round; \
__asm__ __volatile__ ("fldcw\t%0" :: "m" (_cw)); \
unsigned short _fcw; \
__asm__ __volatile__ ("fnstcw\t%0" : "=m" (_fcw)); \
_fcw &= ~FP_RND_MASK; \
_fcw |= round; \
__asm__ __volatile__ ("fldcw\t%0" :: "m" (_fcw)); \
if (__builtin_cpu_supports ("sse")) \
{ \
__asm__ __volatile__ ("%vstmxcsr\t%0" : "=m" (_cw)); \
_cw &= ~0x6000; \
_cw |= round << 3; \
__asm__ __volatile__ ("%vldmxcsr\t%0" :: "m" (_cw)); \
unsigned int _xcw; \
__asm__ __volatile__ ("%vstmxcsr\t%0" : "=m" (_xcw)); \
_xcw &= ~0x6000; \
_xcw |= round << 3; \
__asm__ __volatile__ ("%vldmxcsr\t%0" :: "m" (_xcw)); \
} \
} \
while (0);