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Diffstat (limited to 'gcc/doc/tm.texi')
| -rw-r--r-- | gcc/doc/tm.texi | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/gcc/doc/tm.texi b/gcc/doc/tm.texi index 48f757c6d62..ecc56b4c50c 100644 --- a/gcc/doc/tm.texi +++ b/gcc/doc/tm.texi @@ -6653,6 +6653,18 @@ should probably only be given to addresses with different numbers of registers on machines with lots of registers. @end deftypefn +@deftypefn {Target Hook} int TARGET_INSN_COST (rtx_insn *@var{insn}, bool @var{speed}) +This target hook describes the relative costs of RTL instructions. + +In implementing this hook, you can use the construct +@code{COSTS_N_INSNS (@var{n})} to specify a cost equal to @var{n} fast +instructions. + +When optimizing for code size, i.e.@: when @code{speed} is +false, this target hook should be used to estimate the relative +size cost of an expression, again relative to @code{COSTS_N_INSNS}. +@end deftypefn + @deftypefn {Target Hook} {unsigned int} TARGET_MAX_NOCE_IFCVT_SEQ_COST (edge @var{e}) This hook returns a value in the same units as @code{TARGET_RTX_COSTS}, giving the maximum acceptable cost for a sequence generated by the RTL |