diff options
Diffstat (limited to 'gcc/tree-ssa-ter.c')
| -rw-r--r-- | gcc/tree-ssa-ter.c | 19 |
1 files changed, 10 insertions, 9 deletions
diff --git a/gcc/tree-ssa-ter.c b/gcc/tree-ssa-ter.c index 670d9637539..a93001a985b 100644 --- a/gcc/tree-ssa-ter.c +++ b/gcc/tree-ssa-ter.c @@ -1,5 +1,6 @@ /* Routines for performing Temporary Expression Replacement (TER) in SSA trees. - Copyright (C) 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc. + Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, + Inc. Contributed by Andrew MacLeod <amacleod@redhat.com> This file is part of GCC. @@ -58,7 +59,7 @@ along with GCC; see the file COPYING3. If not see v_9 = (b_5 + 6) * (C * 10) which will then have the ssa_name assigned to regular variables, and the - resulting code which will be passed ot the expander looks something like: + resulting code which will be passed to the expander looks something like: v = (b + 6) * (C * 10) @@ -70,7 +71,7 @@ along with GCC; see the file COPYING3. If not see Although SSA_NAMES themselves don't change, this pass is performed after coalescing has coalesced different SSA_NAMES together, so there could be a definition of an SSA_NAME which is coalesced with a use that causes a - problem. ie + problem, i.e., PHI b_5 = <b_8(2), b_14(1)> <...> @@ -95,8 +96,8 @@ along with GCC; see the file COPYING3. If not see EXPR_DECL_UID bitmap is allocated and set to the base variable UID of the def and any uses in the expression. non-NULL means the expression is being tracked. The UID's themselves are used to prevent TER substitution into - accumulating sequences. - ie + accumulating sequences, i.e., + x = x + y x = x + z x = x + w @@ -124,7 +125,7 @@ along with GCC; see the file COPYING3. If not see a block to clear out the KILL_LIST bitmaps at the end of each block. NEW_REPLACEABLE_DEPENDENCIES is used as a temporary place to store - dependencies which will be reused by the current definition. ALl the uses + dependencies which will be reused by the current definition. All the uses on an expression are processed before anything else is done. If a use is determined to be a replaceable expression AND the current stmt is also going to be replaceable, all the dependencies of this replaceable use will be @@ -137,8 +138,8 @@ along with GCC; see the file COPYING3. If not see a_2's expression 'b_5 + 6' is determined to be replaceable at the use location. It is dependent on the partition 'b_5' is in. This is cached into - the NEW_REPLACEABLE_DEPENDENCIES bitmap. and when v_8 is examined for - replaceablility, it is a candidate, and it is dependent on the partition + the NEW_REPLACEABLE_DEPENDENCIES bitmap, and when v_8 is examined for + replaceability, it is a candidate, and it is dependent on the partition b_5 is in *NOT* a_2, as well as c_4's partition. if v_8 is also replaceable: @@ -520,7 +521,7 @@ kill_virtual_exprs (temp_expr_table_p tab) /* Mark the expression associated with VAR as replaceable, and enter - the defining stmt into the partition_dependencies table TAB. if + the defining stmt into the partition_dependencies table TAB. If MORE_REPLACING is true, accumulate the pending partition dependencies. */ static void |