63 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			C++
		
	
	
			
		
		
	
	
			63 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			C++
		
	
	
#include <ucontext.h>
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namespace factor
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{
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// glibc lies about the contents of the fpstate the kernel provides, hiding the FXSR
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// environment
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struct _fpstate {
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	/* Regular FPU environment */
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	unsigned long   cw;
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	unsigned long   sw;
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	unsigned long   tag;
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	unsigned long   ipoff;
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	unsigned long   cssel;
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	unsigned long   dataoff;
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	unsigned long   datasel;
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	struct _fpreg   _st[8];
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	unsigned short  status;
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	unsigned short  magic;          /* 0xffff = regular FPU data only */
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	/* FXSR FPU environment */
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	unsigned long   _fxsr_env[6];   /* FXSR FPU env is ignored */
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	unsigned long   mxcsr;
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	unsigned long   reserved;
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	struct _fpxreg  _fxsr_st[8];    /* FXSR FPU reg data is ignored */
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	struct _xmmreg  _xmm[8];
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	unsigned long   padding[56];
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};
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#define X86_FXSR_MAGIC          0x0000
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inline static unsigned int uap_fpu_status(void *uap)
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{
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	ucontext_t *ucontext = (ucontext_t *)uap;
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	struct _fpstate *fpregs = (struct _fpstate *)ucontext->uc_mcontext.fpregs;
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	if (fpregs->magic == X86_FXSR_MAGIC)
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	    return fpregs->sw | fpregs->mxcsr;
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	else
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	    return fpregs->sw;
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}
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inline static void uap_clear_fpu_status(void *uap)
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{
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	ucontext_t *ucontext = (ucontext_t *)uap;
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	struct _fpstate *fpregs = (struct _fpstate *)ucontext->uc_mcontext.fpregs;
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	fpregs->sw = 0;
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	if (fpregs->magic == X86_FXSR_MAGIC)
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	    fpregs->mxcsr &= 0xffffffc0;
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}
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#define UAP_STACK_POINTER(ucontext) (((ucontext_t *)ucontext)->uc_mcontext.gregs[7])
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#define UAP_PROGRAM_COUNTER(ucontext) (((ucontext_t *)ucontext)->uc_mcontext.gregs[14])
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#define UAP_SET_TOC_POINTER(uap, ptr) (void)0
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#define CODE_TO_FUNCTION_POINTER(code) (void)0
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#define CODE_TO_FUNCTION_POINTER_CALLBACK(vm, code) (void)0
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#define FUNCTION_CODE_POINTER(ptr) ptr
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#define FUNCTION_TOC_POINTER(ptr) ptr
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#define UAP_STACK_POINTER_TYPE greg_t
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}
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