diff options
Diffstat (limited to 'gcc/doc/passes.texi')
| -rw-r--r-- | gcc/doc/passes.texi | 25 |
1 files changed, 21 insertions, 4 deletions
diff --git a/gcc/doc/passes.texi b/gcc/doc/passes.texi index 8329ddd..693ad31 100644 --- a/gcc/doc/passes.texi +++ b/gcc/doc/passes.texi @@ -771,7 +771,7 @@ branch instructions. The source file for this pass is @file{gcse.c}. This pass attempts to replace conditional branches and surrounding assignments with arithmetic, boolean value producing comparison instructions, and conditional move instructions. In the very last -invocation after reload, it will generate predicated instructions +invocation after reload/LRA, it will generate predicated instructions when supported by the target. The code is located in @file{ifcvt.c}. @item Web construction @@ -842,9 +842,9 @@ source file is @file{regmove.c}. The integrated register allocator (@acronym{IRA}). It is called integrated because coalescing, register live range splitting, and hard register preferencing are done on-the-fly during coloring. It also -has better integration with the reload pass. Pseudo-registers spilled -by the allocator or the reload have still a chance to get -hard-registers if the reload evicts some pseudo-registers from +has better integration with the reload/LRA pass. Pseudo-registers spilled +by the allocator or the reload/LRA have still a chance to get +hard-registers if the reload/LRA evicts some pseudo-registers from hard-registers. The allocator helps to choose better pseudos for spilling based on their live ranges and to coalesce stack slots allocated for the spilled pseudo-registers. IRA is a regional @@ -875,6 +875,23 @@ instructions to save and restore call-clobbered registers around calls. Source files are @file{reload.c} and @file{reload1.c}, plus the header @file{reload.h} used for communication between them. + +@cindex Local Register Allocator (LRA) +@item +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. + +Unlike the reload pass, intermediate LRA decisions are reflected in +RTL as much as possible. This reduces the number of target-dependent +macros and hooks, leaving instruction constraints as the primary +source of control. + +LRA is run on targets for which TARGET_LRA_P returns true. @end itemize @item Basic block reordering |