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author | Andrew Hsieh <andrewhsieh@google.com> | 2014-06-18 13:00:04 -0700 |
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committer | Pavel Chupin <pavel.v.chupin@intel.com> | 2014-06-19 22:38:42 +0400 |
commit | f190d6284359da8ae8694b2d2e14b01602a959ed (patch) | |
tree | d4e0548e7cec02d60b1082368032e66a1c509a02 /gcc-4.8/gcc/tree-ssa-ter.c | |
parent | 4ff2f42147bc128ce38789071d98e55844cd3a5e (diff) | |
download | toolchain_gcc-f190d6284359da8ae8694b2d2e14b01602a959ed.tar.gz toolchain_gcc-f190d6284359da8ae8694b2d2e14b01602a959ed.tar.bz2 toolchain_gcc-f190d6284359da8ae8694b2d2e14b01602a959ed.zip |
Merge GCC 4.8.3
Change-Id: I0abe59f7705b3eccc6b2f123af75b2e30917696a
Diffstat (limited to 'gcc-4.8/gcc/tree-ssa-ter.c')
-rw-r--r-- | gcc-4.8/gcc/tree-ssa-ter.c | 49 |
1 files changed, 46 insertions, 3 deletions
diff --git a/gcc-4.8/gcc/tree-ssa-ter.c b/gcc-4.8/gcc/tree-ssa-ter.c index 2a2e143de..8f27d374b 100644 --- a/gcc-4.8/gcc/tree-ssa-ter.c +++ b/gcc-4.8/gcc/tree-ssa-ter.c @@ -590,6 +590,30 @@ mark_replaceable (temp_expr_table_p tab, tree var, bool more_replacing) } +/* Helper function for find_ssaname_in_stores. Called via walk_tree to + find a SSA_NAME DATA somewhere in *TP. */ + +static tree +find_ssaname (tree *tp, int *walk_subtrees, void *data) +{ + tree var = (tree) data; + if (*tp == var) + return var; + else if (IS_TYPE_OR_DECL_P (*tp)) + *walk_subtrees = 0; + return NULL_TREE; +} + +/* Helper function for find_replaceable_in_bb. Return true if SSA_NAME DATA + is used somewhere in T, which is a store in the statement. Called via + walk_stmt_load_store_addr_ops. */ + +static bool +find_ssaname_in_store (gimple, tree, tree t, void *data) +{ + return walk_tree (&t, find_ssaname, data, NULL) != NULL_TREE; +} + /* This function processes basic block BB, and looks for variables which can be replaced by their expressions. Results are stored in the table TAB. */ @@ -643,8 +667,7 @@ find_replaceable_in_bb (temp_expr_table_p tab, basic_block bb) /* If the stmt does a memory store and the replacement is a load aliasing it avoid creating overlapping assignments which we cannot expand correctly. */ - if (gimple_vdef (stmt) - && gimple_assign_single_p (stmt)) + if (gimple_vdef (stmt)) { gimple def_stmt = SSA_NAME_DEF_STMT (use); while (is_gimple_assign (def_stmt) @@ -653,10 +676,30 @@ find_replaceable_in_bb (temp_expr_table_p tab, basic_block bb) = SSA_NAME_DEF_STMT (gimple_assign_rhs1 (def_stmt)); if (gimple_vuse (def_stmt) && gimple_assign_single_p (def_stmt) - && refs_may_alias_p (gimple_assign_lhs (stmt), + && stmt_may_clobber_ref_p (stmt, gimple_assign_rhs1 (def_stmt))) + { + /* For calls, it is not a problem if USE is among + call's arguments or say OBJ_TYPE_REF argument, + all those necessarily need to be evaluated before + the call that may clobber the memory. But if + LHS of the call refers to USE, expansion might + evaluate it after the call, prevent TER in that + case. + For inline asm, allow TER of loads into input + arguments, but disallow TER for USEs that occur + somewhere in outputs. */ + if (is_gimple_call (stmt) + || gimple_code (stmt) == GIMPLE_ASM) + { + if (walk_stmt_load_store_ops (stmt, use, NULL, + find_ssaname_in_store)) same_root_var = true; } + else + same_root_var = true; + } + } /* Mark expression as replaceable unless stmt is volatile, or the def variable has the same root variable as something in the |