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Diffstat (limited to 'gcc/tm.texi')
| -rw-r--r-- | gcc/tm.texi | 38 |
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diff --git a/gcc/tm.texi b/gcc/tm.texi index 283eb68..4b8193d 100644 --- a/gcc/tm.texi +++ b/gcc/tm.texi @@ -1307,7 +1307,6 @@ For returning values in registers, see @ref{Scalar Return}. * Values in Registers:: What kinds of values each reg can hold. * Leaf Functions:: Renumbering registers for leaf functions. * Stack Registers:: Handling a register stack such as 80387. -* Obsolete Register Macros:: Macros formerly used for the 80387. @end menu @node Register Basics @@ -1689,43 +1688,6 @@ The number of the last stack-like register. This one is the bottom of the stack. @end table -@node Obsolete Register Macros -@subsection Obsolete Macros for Controlling Register Usage - -These features do not work very well. They exist because they used to -be required to generate correct code for the 80387 coprocessor of the -80386. They are no longer used by that machine description and may be -removed in a later version of the compiler. Don't use them! - -@table @code -@findex OVERLAPPING_REGNO_P -@item OVERLAPPING_REGNO_P (@var{regno}) -If defined, this is a C expression whose value is nonzero if hard -register number @var{regno} is an overlapping register. This means a -hard register which overlaps a hard register with a different number. -(Such overlap is undesirable, but occasionally it allows a machine to -be supported which otherwise could not be.) This macro must return -nonzero for @emph{all} the registers which overlap each other. GCC -can use an overlapping register only in certain limited ways. It can -be used for allocation within a basic block, and may be spilled for -reloading; that is all. - -If this macro is not defined, it means that none of the hard registers -overlap each other. This is the usual situation. - -@findex INSN_CLOBBERS_REGNO_P -@item INSN_CLOBBERS_REGNO_P (@var{insn}, @var{regno}) -If defined, this is a C expression whose value should be nonzero if -the insn @var{insn} has the effect of mysteriously clobbering the -contents of hard register number @var{regno}. By ``mysterious'' we -mean that the insn's RTL expression doesn't describe such an effect. - -If this macro is not defined, it means that no insn clobbers registers -mysteriously. This is the usual situation; all else being equal, -it is best for the RTL expression to show all the activity. - -@end table - @node Register Classes @section Register Classes @cindex register class definitions |