#include "postgres.h"
#include <setjmp.h>
#include <signal.h>
#include "port/pg_crc32c.h"

Include dependency graph for pg_crc32c_armv8_choose.c:

Functions
static void	illegal_instruction_handler (SIGNAL_ARGS)

static bool	pg_crc32c_armv8_available (void)

static pg_crc32c	pg_comp_crc32c_choose (pg_crc32c crc, const void *data, size_t len)

Variables
static sigjmp_buf	illegal_instruction_jump

pg_crc32c(*	pg_comp_crc32c )(pg_crc32c crc, const void *data, size_t len) = pg_comp_crc32c_choose

Function Documentation

◆ illegal_instruction_handler()

static void illegal_instruction_handler ( SIGNAL_ARGS )

static

Definition at line 40 of file pg_crc32c_armv8_choose.c.

 {
     siglongjmp(illegal_instruction_jump, 1);
 }

References illegal_instruction_jump.

Referenced by pg_crc32c_armv8_available().

◆ pg_comp_crc32c_choose()

static pg_crc32c pg_comp_crc32c_choose	(	pg_crc32c	crc,
		const void *	data,
		size_t	len
	)

static

Definition at line 85 of file pg_crc32c_armv8_choose.c.

 {
     if (pg_crc32c_armv8_available())
         pg_comp_crc32c = pg_comp_crc32c_armv8;
     else
         pg_comp_crc32c = pg_comp_crc32c_sb8;
  
     return pg_comp_crc32c(crc, data, len);
 }

References crc, data, len, pg_comp_crc32c, pg_comp_crc32c_armv8(), pg_comp_crc32c_sb8(), and pg_crc32c_armv8_available().

◆ pg_crc32c_armv8_available()

static bool pg_crc32c_armv8_available ( void )

static

Definition at line 46 of file pg_crc32c_armv8_choose.c.

 {
     uint64      data = 42;
     int         result;
  
     /*
      * Be careful not to do anything that might throw an error while we have
      * the SIGILL handler set to a nonstandard value.
      */
     pqsignal(SIGILL, illegal_instruction_handler);
     if (sigsetjmp(illegal_instruction_jump, 1) == 0)
     {
         /* Rather than hard-wiring an expected result, compare to SB8 code */
         result = (pg_comp_crc32c_armv8(0, &data, sizeof(data)) ==
                   pg_comp_crc32c_sb8(0, &data, sizeof(data)));
     }
     else
     {
         /* We got the SIGILL trap */
         result = -1;
     }
     pqsignal(SIGILL, SIG_DFL);
  
 #ifndef FRONTEND
     /* We don't expect this case, so complain loudly */
     if (result == 0)
         elog(ERROR, "crc32 hardware and software results disagree");
  
     elog(DEBUG1, "using armv8 crc32 hardware = %d", (result > 0));
 #endif
  
     return (result > 0);
 }