tm.texi.in (TARGET_CLASS_LIKELY_SPILLED_P): Update documentation.

	* doc/tm.texi.in (TARGET_CLASS_LIKELY_SPILLED_P): Update documentation.
	* doc/tm.texi: Regenerate.
	* regs.h (REG_LIVE_LENGTH): Update comments to not refer to no longer
	existing files global.c and local-alloc.c.
	* regmove.c (copy_src_to_dest): Likewise.
	* function.h (struct rtl_data): Likewise.
	* ira-color.c (allocno_priority_compare_func): Likewise.
	* regstat.c (regstat_compute_ri): Likewise.
	* config/epiphany/epiphany.h, config/vax/vax.h, config/cris/cris.h,
	config/h8300/h8300.h, config/alpha/alpha.h, config/sparc/sparc.h,
	config/rs6000/rs6000.h, config/pdp11/pdp11.h, config/pa/pa.h,
	config/v850/v850.h, config/mn10300/mn10300.h, config/m32r/m32r.h,
	config/i386/i386.h, config/mcore/mcore.h, config/sh/sh.h,
	config/arm/arm.h (REGNO_OK_FOR_BASE_P): Likewise.

From-SVN: r194229

2 files changed, 14 insertions, 18 deletions

diff --git a/gcc/doc/tm.texi b/gcc/doc/tm.texi
index f981964..3ab9987 100644
--- a/gcc/doc/tm.texi
+++ b/gcc/doc/tm.texi
@@ -2834,15 +2834,13 @@ registers of @var{rclass} are needed for spill registers.
 
 The default version of this target hook returns @code{true} if @var{rclass}
 has exactly one register and @code{false} otherwise.  On most machines, this
-default should be used.  Only use this target hook to some other expression
-if pseudos allocated by @file{local-alloc.c} end up in memory because their
-hard registers were needed for spill registers.  If this target hook returns
-@code{false} for those classes, those pseudos will only be allocated by
-@file{global.c}, which knows how to reallocate the pseudo to another
-register.  If there would not be another register available for reallocation,
-you should not change the implementation of this target hook since
-the only effect of such implementation would be to slow down register
-allocation.
+default should be used.  For generally register-starved machines, such as
+i386, or machines with right register constraints, such as SH, this hook
+can be used to avoid excessive spilling.
+
+This hook is also used by some of the global intra-procedural code
+transformations to throtle code motion, to avoid increasing register
+pressure.
 @end deftypefn
 
 @deftypefn {Target Hook} {unsigned char} TARGET_CLASS_MAX_NREGS (reg_class_t @var{rclass}, enum machine_mode @var{mode})
diff --git a/gcc/doc/tm.texi.in b/gcc/doc/tm.texi.in
index 7a93f21..6d48fe4 100644
--- a/gcc/doc/tm.texi.in
+++ b/gcc/doc/tm.texi.in
@@ -2810,15 +2810,13 @@ registers of @var{rclass} are needed for spill registers.
 
 The default version of this target hook returns @code{true} if @var{rclass}
 has exactly one register and @code{false} otherwise.  On most machines, this
-default should be used.  Only use this target hook to some other expression
-if pseudos allocated by @file{local-alloc.c} end up in memory because their
-hard registers were needed for spill registers.  If this target hook returns
-@code{false} for those classes, those pseudos will only be allocated by
-@file{global.c}, which knows how to reallocate the pseudo to another
-register.  If there would not be another register available for reallocation,
-you should not change the implementation of this target hook since
-the only effect of such implementation would be to slow down register
-allocation.
+default should be used.  For generally register-starved machines, such as
+i386, or machines with right register constraints, such as SH, this hook
+can be used to avoid excessive spilling.
+
+This hook is also used by some of the global intra-procedural code
+transformations to throtle code motion, to avoid increasing register
+pressure.
 @end deftypefn
 
 @hook TARGET_CLASS_MAX_NREGS