common.opt (flra-remat): New.

2014-11-12  Vladimir Makarov  <vmakarov@redhat.com>

	* common.opt (flra-remat): New.
	* opts.c (default_options_table): Add entry for flra_remat.
	* timevar_def (TV_LRA_REMAT): New.
	* doc/invoke.texi (-flra-remat): Add description of the new
	option.
	* doc/passes.texi (-flra-remat): Remove lra-equivs.c and
	lra-saves.c.  Add lra-remat.c.
	* Makefile.in (OBJS): Add lra-remat.o.
	* lra-remat.c: New file.
	* lra.c: Add info about the rematerialization pass in the top
	comment.
	(collect_non_operand_hard_regs, add_regs_to_insn_regno_info):
	Process unallocatable regs too.
	(lra_constraint_new_insn_uid_start): Remove.
	(lra): Add code for calling rematerialization sub-pass.
	* lra-int.h (lra_constraint_new_insn_uid_start): Remove.
	(lra_constrain_insn, lra_remat): New prototypes.
	(lra_eliminate_regs_1): Add parameter.
	* lra-lives.c (make_hard_regno_born, make_hard_regno_dead):
	Process unallocatable hard regs too.
	(process_bb_lives): Ditto.
	* lra-spills.c (remove_pseudos): Add argument to
	lra_eliminate_regs_1 call.
	* lra-eliminations.c (lra_eliminate_regs_1): Add parameter.  Use it
	for sp offset calculation.
	(lra_eliminate_regs): Add argument for lra_eliminate_regs_1 call.
	(eliminate_regs_in_insn): Add parameter.  Use it for sp offset
	calculation.
	(process_insn_for_elimination): Add argument for
	eliminate_regs_in_insn call.
	* lra-constraints.c (get_equiv_with_elimination):  Add argument
	for lra_eliminate_regs_1 call.
	(process_addr_reg): Add parameter.  Use it.
	(process_address_1): Ditto.  Add argument for process_addr_reg
	call.
	(process_address): Ditto.
	(curr_insn_transform): Add parameter.  Use it.  Add argument for
	process_address calls.
	(lra_constrain_insn): New function.
	(lra_constraints): Add argument for curr_insn_transform call.

From-SVN: r217458

2 files changed, 14 insertions, 5 deletions

diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 294e17d..12dbb27 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -392,7 +392,7 @@ Objective-C and Objective-C++ Dialects}.
 -fisolate-erroneous-paths-dereference -fisolate-erroneous-paths-attribute @gol
 -fivopts -fkeep-inline-functions -fkeep-static-consts -flive-range-shrinkage @gol
 -floop-block -floop-interchange -floop-strip-mine -floop-nest-optimize @gol
--floop-parallelize-all -flto -flto-compression-level @gol
+-floop-parallelize-all -flra-remat -flto -flto-compression-level @gol
 -flto-partition=@var{alg} -flto-report -flto-report-wpa -fmerge-all-constants @gol
 -fmerge-constants -fmodulo-sched -fmodulo-sched-allow-regmoves @gol
 -fmove-loop-invariants -fno-branch-count-reg @gol
@@ -7183,6 +7183,7 @@ also turns on the following optimization flags:
 -fipa-sra @gol
 -fipa-icf @gol
 -fisolate-erroneous-paths-dereference @gol
+-flra-remat @gol
 -foptimize-sibling-calls @gol
 -foptimize-strlen @gol
 -fpartial-inlining @gol
@@ -7811,6 +7812,14 @@ Control the verbosity of the dump file for the integrated register allocator.
 The default value is 5.  If the value @var{n} is greater or equal to 10,
 the dump output is sent to stderr using the same format as @var{n} minus 10.
 
+@item -flra-remat
+@opindex fcaller-saves
+Enable CFG-sensitive rematerialization in LRA.  Instead of loading
+values of spilled pseudos, LRA tries to rematerialize (recalculate)
+values if it is profitable.
+
+Enabled at levels @option{-O2}, @option{-O3}, @option{-Os}.
+
 @item -fdelayed-branch
 @opindex fdelayed-branch
 If supported for the target machine, attempt to reorder instructions
diff --git a/gcc/doc/passes.texi b/gcc/doc/passes.texi
index 0ab8f21..090eb0a 100644
--- a/gcc/doc/passes.texi
+++ b/gcc/doc/passes.texi
@@ -911,10 +911,10 @@ Source files are @file{reload.c} and @file{reload1.c}, plus the header
 This pass is a modern replacement of the reload pass.  Source files
 are @file{lra.c}, @file{lra-assign.c}, @file{lra-coalesce.c},
 @file{lra-constraints.c}, @file{lra-eliminations.c},
-@file{lra-equivs.c}, @file{lra-lives.c}, @file{lra-saves.c},
-@file{lra-spills.c}, the header @file{lra-int.h} used for
-communication between them, and the header @file{lra.h} used for
-communication between LRA and the rest of compiler.
+@file{lra-lives.c}, @file{lra-remat.c}, @file{lra-spills.c}, the
+header @file{lra-int.h} used for communication between them, and the
+header @file{lra.h} used for communication between LRA and the rest of
+compiler.
 
 Unlike the reload pass, intermediate LRA decisions are reflected in
 RTL as much as possible.  This reduces the number of target-dependent