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Diffstat (limited to 'gcc-4.8/gcc/doc/tm.texi')
| -rw-r--r-- | gcc-4.8/gcc/doc/tm.texi | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/gcc-4.8/gcc/doc/tm.texi b/gcc-4.8/gcc/doc/tm.texi index cbbc82dfe..48df7ce24 100644 --- a/gcc-4.8/gcc/doc/tm.texi +++ b/gcc-4.8/gcc/doc/tm.texi @@ -9914,6 +9914,43 @@ default, inlining is not allowed if the callee function has function specific target options and the caller does not use the same options. @end deftypefn +@deftypefn {Target Hook} rtx TARGET_GET_PIC_REG (void) +Return the pic_reg pseudo register which holds the base address of GOT. + It is only required by the simplify-got optimization. +@end deftypefn + +@deftypefn {Target Hook} void TARGET_CLEAR_PIC_REG (void) +After successful simplify-got optimization, the pic_reg is useless. So a + target can use this hook to clear pic_reg. +@end deftypefn + +@deftypefn {Target Hook} rtx TARGET_LOADED_GLOBAL_VAR (rtx @var{insn}, rtx *@var{offset_reg}, rtx *@var{offset_insn}) +This hook is used to detect if the given @var{insn} loads a global + variable's address from GOT with the form of + @smallexample + (set @var{address_reg} (mem (plus pic_reg @var{offset_reg}))) + @end smallexample + If so return the global variable whose address will be loaded and fill in + @var{offset_insn} and @var{offset_reg}. @var{offset_reg} is set at + @var{offset_insn} to hold the offset from GOT base to the GOT entry of the + global variable. Otherwise return @code{NULL_RTX}. +@end deftypefn + +@deftypefn {Target Hook} bool TARGET_CAN_SIMPLIFY_GOT_ACCESS (int @var{n_symbol}, int @var{n_access}) +This hook determines if it satisfy the target dependent conditions to do + simplify-got when given the number of global variable accessing and the + number of accessed symbols. If the returned value is false the GOT access + insns will not be rewritten. Otherwise we will rewrite these insns. +@end deftypefn + +@deftypefn {Target Hook} void TARGET_LOAD_GLOBAL_ADDRESS (rtx @var{symbol}, rtx @var{offset_reg}, rtx @var{address_reg}, rtx @var{load_insn}, rtx @var{offset_insn}) +This hook does the actual rewriting of GOT access insn @var{load_insn}. + The global variable is @var{symbol}. The global address should be loaded + into @var{address_reg}. The register @var{offset_reg} was previously set + in insn @var{offset_insn} to hold the offset from GOT base to the GOT + entry of the global variable. Now it can be used as a scratch register. +@end deftypefn + @node Emulated TLS @section Emulating TLS @cindex Emulated TLS |