diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr72835.c b/gcc/testsuite/gcc.dg/tree-ssa/pr72835.c index e69de29..049eddc 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/pr72835.c +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr72835.c @@ -0,0 +1,36 @@ +/* PR tree-optimization/72835. */ +/* { dg-do run } */ +/* { dg-options "-O2" } */ + +struct struct_1 { + unsigned int m1 : 6 ; + unsigned int m2 : 24 ; + unsigned int m3 : 6 ; +}; + +unsigned short var_32 = 0x2d10; + +struct struct_1 s1; + +void init () +{ + s1.m1 = 4; + s1.m2 = 0x7ca4b8; + s1.m3 = 24; +} + +void foo () +{ + unsigned int c + = ((unsigned int) s1.m2) * (-((unsigned int) s1.m3)) + + (var_32) * (-((unsigned int) (s1.m1))); + if (c != 4098873984) + __builtin_abort (); +} + +int main () +{ + init (); + foo (); + return 0; +} diff --git a/gcc/tree-ssa-reassoc.c b/gcc/tree-ssa-reassoc.c index 7fd7550..c7f6a66 100644 --- a/gcc/tree-ssa-reassoc.c +++ b/gcc/tree-ssa-reassoc.c @@ -1148,6 +1148,49 @@ decrement_power (gimple *stmt) } } +/* Replace SSA defined by STMT and replace all its uses with new + SSA. Also return the new SSA. */ + +static tree +make_new_ssa_for_def (gimple *stmt) +{ + gimple *use_stmt; + use_operand_p use; + imm_use_iterator iter; + tree new_lhs; + tree lhs = gimple_assign_lhs (stmt); + gcc_assert (has_single_use (lhs)); + + new_lhs = make_ssa_name (TREE_TYPE (lhs)); + gimple_set_lhs (stmt, new_lhs); + + /* Also need to update GIMPLE_DEBUGs. */ + FOR_EACH_IMM_USE_STMT (use_stmt, iter, lhs) + { + FOR_EACH_IMM_USE_ON_STMT (use, iter) + SET_USE (use, new_lhs); + update_stmt (use_stmt); + } + return new_lhs; +} + +/* Replace all SSAs defined in STMTS_TO_FIX and replace its + uses with new SSAs. Also do this for the stmt that defines DEF + if *DEF is not OP. */ + +static void +make_new_ssa_for_all_defs (tree *def, tree op, + auto_vec &stmts_to_fix) +{ + unsigned i; + gimple *stmt = SSA_NAME_DEF_STMT (*def); + if (*def != op + && gimple_code (stmt) != GIMPLE_NOP) + *def = make_new_ssa_for_def (stmt); + FOR_EACH_VEC_ELT (stmts_to_fix, i, stmt) + make_new_ssa_for_def (stmt); +} + /* Find the single immediate use of STMT's LHS, and replace it with OP. Remove STMT. If STMT's LHS is the same as *DEF, replace *DEF with OP as well. */ @@ -1186,6 +1229,9 @@ static void zero_one_operation (tree *def, enum tree_code opcode, tree op) { gimple *stmt = SSA_NAME_DEF_STMT (*def); + /* PR72835 - Record the stmt chain that has to be updated such that + we dont use the same LHS when the values computed are different. */ + auto_vec stmts_to_fix; do { @@ -1195,6 +1241,7 @@ zero_one_operation (tree *def, enum tree_code opcode, tree op) { if (stmt_is_power_of_op (stmt, op)) { + make_new_ssa_for_all_defs (def, op, stmts_to_fix); if (decrement_power (stmt) == 1) propagate_op_to_single_use (op, stmt, def); return; @@ -1204,6 +1251,7 @@ zero_one_operation (tree *def, enum tree_code opcode, tree op) if (gimple_assign_rhs1 (stmt) == op) { tree cst = build_minus_one_cst (TREE_TYPE (op)); + make_new_ssa_for_all_defs (def, op, stmts_to_fix); propagate_op_to_single_use (cst, stmt, def); return; } @@ -1212,6 +1260,7 @@ zero_one_operation (tree *def, enum tree_code opcode, tree op) { gimple_assign_set_rhs_code (stmt, TREE_CODE (gimple_assign_rhs1 (stmt))); + make_new_ssa_for_all_defs (def, op, stmts_to_fix); return; } } @@ -1228,6 +1277,7 @@ zero_one_operation (tree *def, enum tree_code opcode, tree op) { if (name == op) name = gimple_assign_rhs2 (stmt); + make_new_ssa_for_all_defs (def, op, stmts_to_fix); propagate_op_to_single_use (name, stmt, def); return; } @@ -1243,6 +1293,8 @@ zero_one_operation (tree *def, enum tree_code opcode, tree op) gimple *stmt2 = SSA_NAME_DEF_STMT (gimple_assign_rhs2 (stmt)); if (stmt_is_power_of_op (stmt2, op)) { + stmts_to_fix.safe_push (stmt2); + make_new_ssa_for_all_defs (def, op, stmts_to_fix); if (decrement_power (stmt2) == 1) propagate_op_to_single_use (op, stmt2, def); return; @@ -1253,14 +1305,18 @@ zero_one_operation (tree *def, enum tree_code opcode, tree op) if (gimple_assign_rhs1 (stmt2) == op) { tree cst = build_minus_one_cst (TREE_TYPE (op)); + stmts_to_fix.safe_push (stmt2); + make_new_ssa_for_all_defs (def, op, stmts_to_fix); propagate_op_to_single_use (cst, stmt2, def); return; } else if (integer_minus_onep (op) || real_minus_onep (op)) { + stmts_to_fix.safe_push (stmt2); gimple_assign_set_rhs_code (stmt2, TREE_CODE (gimple_assign_rhs1 (stmt2))); + make_new_ssa_for_all_defs (def, op, stmts_to_fix); return; } } @@ -1270,6 +1326,7 @@ zero_one_operation (tree *def, enum tree_code opcode, tree op) gcc_assert (name != op && TREE_CODE (name) == SSA_NAME); stmt = SSA_NAME_DEF_STMT (name); + stmts_to_fix.safe_push (stmt); } while (1); }