61 lines
1.5 KiB
C
61 lines
1.5 KiB
C
/* crt0.c.
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Copyright 2001 Red Hat, Inc.
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This software is a copyrighted work licensed under the terms of the
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Cygwin license. Please consult the file "CYGWIN_LICENSE" for
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details. */
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#ifdef __PPC__
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/* For the PowerPC, we want to make this function have its structured
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exception table exception function point to something we control. */
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extern void __cygwin_exception_handler();
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extern void mainCRTStartup(void) __attribute__((__exception__(__cygwin_exception_handler)));
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#endif
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/* In the following ifdef'd i386 code, the FPU precision is set to 80 bits
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and all FPU exceptions are masked. The former is needed to make long
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doubles work correctly. The latter causes the FPU to generate NaNs and
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Infinities instead of signals for certain operations.
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*/
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#ifdef __i386__
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#define FPU_RESERVED 0xF0C0
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#define FPU_DEFAULT 0x033f
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/* For debugging on *#!$@ windbg. bp for breakpoint. */
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int __cygwin_crt0_bp = 0;
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#endif
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extern int main (int argc, char **argv);
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void cygwin_crt0 (int (*main) (int, char **));
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void
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mainCRTStartup ()
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{
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#ifdef __i386__
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(void)__builtin_return_address(1);
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asm volatile ("andl $-16,%%esp" ::: "%esp");
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if (__cygwin_crt0_bp)
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asm volatile ("int3");
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{
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volatile unsigned short cw;
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/* Get Control Word */
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__asm__ volatile ("fnstcw %0" : "=m" (cw) : );
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/* mask in */
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cw &= FPU_RESERVED;
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cw |= FPU_DEFAULT;
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/* set cw */
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__asm__ volatile ("fldcw %0" :: "m" (cw));
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}
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#endif
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cygwin_crt0 (main);
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}
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