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|
--- /dev/null
+++ b/make/target/gcc/4.7.0/920-tree-ssa-tail-merge.patch
@@ -0,0 +1,244 @@
+This patch refers to:
+
+http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52734
+http://gcc.gnu.org/bugzilla/attachment.cgi?id=27014&action=diff&context=patch&collapsed=&headers=1&format=raw
+
+--- gcc/tree-ssa-tail-merge.c
++++ gcc/tree-ssa-tail-merge.c
+@@ -1033,7 +1033,7 @@ set_cluster (basic_block bb1, basic_bloc
+ gimple_bb (s2) are members of SAME_SUCC. */
+
+ static bool
+-gimple_equal_p (same_succ same_succ, gimple s1, gimple s2)
++gimple_equal_p (same_succ same_succ, gimple s1, gimple s2, bool *gvn_used)
+ {
+ unsigned int i;
+ tree lhs1, lhs2;
+@@ -1069,7 +1069,10 @@ gimple_equal_p (same_succ same_succ, gim
+ if (operand_equal_p (t1, t2, 0))
+ continue;
+ if (gvn_uses_equal (t1, t2))
+- continue;
++ {
++ *gvn_used = true;
++ continue;
++ }
+ equal = false;
+ break;
+ }
+@@ -1083,12 +1086,16 @@ gimple_equal_p (same_succ same_succ, gim
+ if (lhs1 == NULL_TREE || lhs2 == NULL_TREE)
+ return false;
+ if (TREE_CODE (lhs1) == SSA_NAME && TREE_CODE (lhs2) == SSA_NAME)
+- return vn_valueize (lhs1) == vn_valueize (lhs2);
++ {
++ *gvn_used = true;
++ return vn_valueize (lhs1) == vn_valueize (lhs2);
++ }
+ return operand_equal_p (lhs1, lhs2, 0);
+
+ case GIMPLE_ASSIGN:
+ lhs1 = gimple_get_lhs (s1);
+ lhs2 = gimple_get_lhs (s2);
++ *gvn_used = true;
+ return (TREE_CODE (lhs1) == SSA_NAME
+ && TREE_CODE (lhs2) == SSA_NAME
+ && vn_valueize (lhs1) == vn_valueize (lhs2));
+@@ -1096,15 +1103,23 @@ gimple_equal_p (same_succ same_succ, gim
+ case GIMPLE_COND:
+ t1 = gimple_cond_lhs (s1);
+ t2 = gimple_cond_lhs (s2);
+- if (!operand_equal_p (t1, t2, 0)
+- && !gvn_uses_equal (t1, t2))
+- return false;
++ if (!operand_equal_p (t1, t2, 0))
++ {
++ if (gvn_uses_equal (t1, t2))
++ *gvn_used = true;
++ else
++ return false;
++ }
+
+ t1 = gimple_cond_rhs (s1);
+ t2 = gimple_cond_rhs (s2);
+- if (!operand_equal_p (t1, t2, 0)
+- && !gvn_uses_equal (t1, t2))
+- return false;
++ if (!operand_equal_p (t1, t2, 0))
++ {
++ if (gvn_uses_equal (t1, t2))
++ *gvn_used = true;
++ else
++ return false;
++ }
+
+ code1 = gimple_expr_code (s1);
+ code2 = gimple_expr_code (s2);
+@@ -1126,18 +1141,25 @@ gimple_equal_p (same_succ same_succ, gim
+ /* Let GSI skip backwards over local defs. */
+
+ static void
+-gsi_advance_bw_nondebug_nonlocal (gimple_stmt_iterator *gsi)
++gsi_advance_bw_nondebug_nonlocal (gimple_stmt_iterator *gsi, tree *vuse)
+ {
+ gimple stmt;
++ tree lvuse;
+
+ while (true)
+ {
+ if (gsi_end_p (*gsi))
+ return;
+ stmt = gsi_stmt (*gsi);
++
++ lvuse = gimple_vuse (stmt);
++ if (lvuse != NULL_TREE)
++ *vuse = lvuse;
++
+ if (!(is_gimple_assign (stmt) && local_def (gimple_get_lhs (stmt))
+ && !gimple_has_side_effects (stmt)))
+ return;
++
+ gsi_prev_nondebug (gsi);
+ }
+ }
+@@ -1146,28 +1168,34 @@ gsi_advance_bw_nondebug_nonlocal (gimple
+ clusters them. */
+
+ static void
+-find_duplicate (same_succ same_succ, basic_block bb1, basic_block bb2)
++find_duplicate (same_succ same_succ, basic_block bb1, basic_block bb2,
++ bool gvn_used)
+ {
+ gimple_stmt_iterator gsi1 = gsi_last_nondebug_bb (bb1);
+ gimple_stmt_iterator gsi2 = gsi_last_nondebug_bb (bb2);
++ tree vuse1 = NULL_TREE, vuse2 = NULL_TREE;
+
+- gsi_advance_bw_nondebug_nonlocal (&gsi1);
+- gsi_advance_bw_nondebug_nonlocal (&gsi2);
++ gsi_advance_bw_nondebug_nonlocal (&gsi1, &vuse1);
++ gsi_advance_bw_nondebug_nonlocal (&gsi2, &vuse2);
+
+ while (!gsi_end_p (gsi1) && !gsi_end_p (gsi2))
+ {
+- if (!gimple_equal_p (same_succ, gsi_stmt (gsi1), gsi_stmt (gsi2)))
++ if (!gimple_equal_p (same_succ, gsi_stmt (gsi1), gsi_stmt (gsi2),
++ &gvn_used))
+ return;
+
+ gsi_prev_nondebug (&gsi1);
+ gsi_prev_nondebug (&gsi2);
+- gsi_advance_bw_nondebug_nonlocal (&gsi1);
+- gsi_advance_bw_nondebug_nonlocal (&gsi2);
++ gsi_advance_bw_nondebug_nonlocal (&gsi1, &vuse1);
++ gsi_advance_bw_nondebug_nonlocal (&gsi2, &vuse2);
+ }
+
+ if (!(gsi_end_p (gsi1) && gsi_end_p (gsi2)))
+ return;
+
++ if (gvn_used && vuse1 != vuse2)
++ return;
++
+ if (dump_file)
+ fprintf (dump_file, "find_duplicates: <bb %d> duplicate of <bb %d>\n",
+ bb1->index, bb2->index);
+@@ -1179,7 +1207,7 @@ find_duplicate (same_succ same_succ, bas
+ E2 are equal. */
+
+ static bool
+-same_phi_alternatives_1 (basic_block dest, edge e1, edge e2)
++same_phi_alternatives_1 (basic_block dest, edge e1, edge e2, bool *gvn_used)
+ {
+ int n1 = e1->dest_idx, n2 = e2->dest_idx;
+ gimple_stmt_iterator gsi;
+@@ -1197,7 +1225,10 @@ same_phi_alternatives_1 (basic_block des
+ if (operand_equal_for_phi_arg_p (val1, val2))
+ continue;
+ if (gvn_uses_equal (val1, val2))
+- continue;
++ {
++ *gvn_used = true;
++ continue;
++ }
+
+ return false;
+ }
+@@ -1209,7 +1240,8 @@ same_phi_alternatives_1 (basic_block des
+ phi alternatives for BB1 and BB2 are equal. */
+
+ static bool
+-same_phi_alternatives (same_succ same_succ, basic_block bb1, basic_block bb2)
++same_phi_alternatives (same_succ same_succ, basic_block bb1, basic_block bb2,
++ bool *gvn_used)
+ {
+ unsigned int s;
+ bitmap_iterator bs;
+@@ -1227,7 +1259,7 @@ same_phi_alternatives (same_succ same_su
+
+ /* For all phis in bb, the phi alternatives for e1 and e2 need to have
+ the same value. */
+- if (!same_phi_alternatives_1 (succ, e1, e2))
++ if (!same_phi_alternatives_1 (succ, e1, e2, gvn_used))
+ return false;
+ }
+
+@@ -1301,6 +1333,7 @@ find_clusters_1 (same_succ same_succ)
+ bitmap_iterator bi, bj;
+ int nr_comparisons;
+ int max_comparisons = PARAM_VALUE (PARAM_MAX_TAIL_MERGE_COMPARISONS);
++ bool gvn_used;
+
+ EXECUTE_IF_SET_IN_BITMAP (same_succ->bbs, 0, i, bi)
+ {
+@@ -1333,10 +1366,11 @@ find_clusters_1 (same_succ same_succ)
+ if (!deps_ok_for_redirect (bb1, bb2))
+ continue;
+
+- if (!(same_phi_alternatives (same_succ, bb1, bb2)))
++ gvn_used = false;
++ if (!(same_phi_alternatives (same_succ, bb1, bb2, &gvn_used)))
+ continue;
+
+- find_duplicate (same_succ, bb1, bb2);
++ find_duplicate (same_succ, bb1, bb2, gvn_used);
+ }
+ }
+ }
+--- gcc/testsuite/gcc.dg/pr52734.c
++++ gcc/testsuite/gcc.dg/pr52734.c
+@@ -0,0 +1,35 @@
++/* { dg-do run } */
++/* { dg-options "-O2" } */
++
++int bbb = 0;
++
++int __attribute__((noinline,noclone)) aaa(void)
++{
++ ++bbb;
++ return 0;
++}
++
++int __attribute__((noinline,noclone)) ccc(void)
++{
++ int ddd;
++ /* bbb == 0 */
++ if (aaa())
++ return bbb;
++
++ /* bbb == 1 */
++ ddd = bbb;
++ /* bbb == ddd == 1 */
++ if (aaa ())
++ return 0;
++ /* bbb == 2, ddd == 1 */
++
++ return ddd;
++}
++
++int main(void)
++{
++ if (ccc() != 1)
++ __builtin_abort();
++ return 0;
++}
++
|
