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-rw-r--r--toolchain/gcc/patches/4.8.2/miscompile.sparc154
1 files changed, 154 insertions, 0 deletions
diff --git a/toolchain/gcc/patches/4.8.2/miscompile.sparc b/toolchain/gcc/patches/4.8.2/miscompile.sparc
new file mode 100644
index 000000000..4aef2e605
--- /dev/null
+++ b/toolchain/gcc/patches/4.8.2/miscompile.sparc
@@ -0,0 +1,154 @@
+diff -Nur gcc-4.8.2.orig/gcc/tree-ssa-forwprop.c gcc-4.8.2/gcc/tree-ssa-forwprop.c
+--- gcc-4.8.2.orig/gcc/tree-ssa-forwprop.c 2013-02-25 16:31:31.000000000 +0100
++++ gcc-4.8.2/gcc/tree-ssa-forwprop.c 2014-03-22 19:37:04.797991879 +0100
+@@ -688,6 +688,130 @@
+ recompute_tree_invariant_for_addr_expr (gimple_assign_rhs1 (stmt));
+ }
+
++ /* DEF_RHS contains the address of the 0th element in an array.
++ USE_STMT uses type of DEF_RHS to compute the address of an
++ arbitrary element within the array. The (variable) byte offset
++ of the element is contained in OFFSET.
++
++ We walk back through the use-def chains of OFFSET to verify that
++ it is indeed computing the offset of an element within the array
++ and extract the index corresponding to the given byte offset.
++
++ We then try to fold the entire address expression into a form
++ &array[index].
++
++ If we are successful, we replace the right hand side of USE_STMT
++ with the new address computation. */
++
++ static bool
++ forward_propagate_addr_into_variable_array_index (tree offset,
++ tree def_rhs,
++ gimple_stmt_iterator *use_stmt_gsi)
++ {
++ tree index, tunit;
++ gimple offset_def, use_stmt = gsi_stmt (*use_stmt_gsi);
++ tree new_rhs, tmp;
++
++ if (TREE_CODE (TREE_OPERAND (def_rhs, 0)) == ARRAY_REF)
++ tunit = TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (def_rhs)));
++ else if (TREE_CODE (TREE_TYPE (TREE_OPERAND (def_rhs, 0))) == ARRAY_TYPE)
++ tunit = TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (TREE_TYPE (def_rhs))));
++ else
++ return false;
++ if (!host_integerp (tunit, 1))
++ return false;
++
++ /* Get the offset's defining statement. */
++ offset_def = SSA_NAME_DEF_STMT (offset);
++
++ /* Try to find an expression for a proper index. This is either a
++ multiplication expression by the element size or just the ssa name we came
++ along in case the element size is one. In that case, however, we do not
++ allow multiplications because they can be computing index to a higher
++ level dimension (PR 37861). */
++ if (integer_onep (tunit))
++ {
++ if (is_gimple_assign (offset_def)
++ && gimple_assign_rhs_code (offset_def) == MULT_EXPR)
++ return false;
++
++ index = offset;
++ }
++ else
++ {
++ /* The statement which defines OFFSET before type conversion
++ must be a simple GIMPLE_ASSIGN. */
++ if (!is_gimple_assign (offset_def))
++ return false;
++
++ /* The RHS of the statement which defines OFFSET must be a
++ multiplication of an object by the size of the array elements.
++ This implicitly verifies that the size of the array elements
++ is constant. */
++ if (gimple_assign_rhs_code (offset_def) == MULT_EXPR
++ && TREE_CODE (gimple_assign_rhs2 (offset_def)) == INTEGER_CST
++ && tree_int_cst_equal (gimple_assign_rhs2 (offset_def), tunit))
++ {
++ /* The first operand to the MULT_EXPR is the desired index. */
++ index = gimple_assign_rhs1 (offset_def);
++ }
++ /* If we have idx * tunit + CST * tunit re-associate that. */
++ else if ((gimple_assign_rhs_code (offset_def) == PLUS_EXPR
++ || gimple_assign_rhs_code (offset_def) == MINUS_EXPR)
++ && TREE_CODE (gimple_assign_rhs1 (offset_def)) == SSA_NAME
++ && TREE_CODE (gimple_assign_rhs2 (offset_def)) == INTEGER_CST
++ && (tmp = div_if_zero_remainder (EXACT_DIV_EXPR,
++ gimple_assign_rhs2 (offset_def),
++ tunit)) != NULL_TREE)
++ {
++ gimple offset_def2 = SSA_NAME_DEF_STMT (gimple_assign_rhs1 (offset_def));
++ if (is_gimple_assign (offset_def2)
++ && gimple_assign_rhs_code (offset_def2) == MULT_EXPR
++ && TREE_CODE (gimple_assign_rhs2 (offset_def2)) == INTEGER_CST
++ && tree_int_cst_equal (gimple_assign_rhs2 (offset_def2), tunit))
++ {
++ index = fold_build2 (gimple_assign_rhs_code (offset_def),
++ TREE_TYPE (offset),
++ gimple_assign_rhs1 (offset_def2), tmp);
++ }
++ else
++ return false;
++ }
++ else
++ return false;
++ }
++
++ /* Replace the pointer addition with array indexing. */
++ index = force_gimple_operand_gsi (use_stmt_gsi, index, true, NULL_TREE,
++ true, GSI_SAME_STMT);
++ if (TREE_CODE (TREE_OPERAND (def_rhs, 0)) == ARRAY_REF)
++ {
++ new_rhs = unshare_expr (def_rhs);
++ TREE_OPERAND (TREE_OPERAND (new_rhs, 0), 1) = index;
++ }
++ else
++ {
++ new_rhs = build4 (ARRAY_REF, TREE_TYPE (TREE_TYPE (TREE_TYPE (def_rhs))),
++ unshare_expr (TREE_OPERAND (def_rhs, 0)),
++ index, integer_zero_node, NULL_TREE);
++ new_rhs = build_fold_addr_expr (new_rhs);
++ if (!useless_type_conversion_p (TREE_TYPE (gimple_assign_lhs (use_stmt)),
++ TREE_TYPE (new_rhs)))
++ {
++ new_rhs = force_gimple_operand_gsi (use_stmt_gsi, new_rhs, true,
++ NULL_TREE, true, GSI_SAME_STMT);
++ new_rhs = fold_convert (TREE_TYPE (gimple_assign_lhs (use_stmt)),
++ new_rhs);
++ }
++ }
++ gimple_assign_set_rhs_from_tree (use_stmt_gsi, new_rhs);
++ fold_stmt (use_stmt_gsi);
++ tidy_after_forward_propagate_addr (gsi_stmt (*use_stmt_gsi));
++ return true;
++ }
++
++
++
+ /* NAME is a SSA_NAME representing DEF_RHS which is of the form
+ ADDR_EXPR <whatever>.
+
+@@ -977,6 +1101,19 @@
+ tidy_after_forward_propagate_addr (use_stmt);
+ return true;
+ }
++ /* Try to optimize &x[0] p+ OFFSET where OFFSET is defined by
++ converting a multiplication of an index by the size of the
++ array elements, then the result is converted into the proper
++ type for the arithmetic. */
++ if (TREE_CODE (rhs2) == SSA_NAME
++ && (TREE_CODE (array_ref) != ARRAY_REF
++ || integer_zerop (TREE_OPERAND (array_ref, 1)))
++ && useless_type_conversion_p (TREE_TYPE (name), TREE_TYPE (def_rhs))
++ /* Avoid problems with IVopts creating PLUS_EXPRs with a
++ different type than their operands. */
++ && useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (def_rhs)))
++ return forward_propagate_addr_into_variable_array_index (rhs2, def_rhs,
++ use_stmt_gsi);
+
+ return false;
+ }