diff options
Diffstat (limited to 'gcc/doc/tm.texi')
| -rw-r--r-- | gcc/doc/tm.texi | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/gcc/doc/tm.texi b/gcc/doc/tm.texi index 799a0f854d3..af269f2a97c 100644 --- a/gcc/doc/tm.texi +++ b/gcc/doc/tm.texi @@ -9314,11 +9314,15 @@ from shared libraries (DLLs). You need not define this macro if it would always evaluate to zero. @end defmac -@deftypefn {Target Hook} tree TARGET_MD_ASM_CLOBBERS (tree @var{clobbers}) +@deftypefn {Target Hook} tree TARGET_MD_ASM_CLOBBERS (tree @var{outputs}, tree @var{inputs}, tree @var{clobbers}) This target hook should add to @var{clobbers} @code{STRING_CST} trees for -any hard regs the port wishes to automatically clobber for all asms. +any hard regs the port wishes to automatically clobber for an asm. It should return the result of the last @code{tree_cons} used to add a -clobber. +clobber. The @var{outputs}, @var{inputs} and @var{clobber} lists are the +corresponding parameters to the asm and may be inspected to avoid +clobbering a register that is an input or output of the asm. You can use +@code{decl_overlaps_hard_reg_set_p}, declared in @file{tree.h}, to test +for overlap with regards to asm-declared registers. @end deftypefn @defmac MATH_LIBRARY |