diff options
Diffstat (limited to 'gcc/tree-tailcall.c')
| -rw-r--r-- | gcc/tree-tailcall.c | 34 |
1 files changed, 27 insertions, 7 deletions
diff --git a/gcc/tree-tailcall.c b/gcc/tree-tailcall.c index a6c44933f79..34ac8ee5834 100644 --- a/gcc/tree-tailcall.c +++ b/gcc/tree-tailcall.c @@ -431,15 +431,27 @@ find_tail_calls (basic_block bb, struct tailcall **ret) param = TREE_CHAIN (param), args = TREE_CHAIN (args)) { tree arg = TREE_VALUE (args); - if (param != arg - /* Make sure there are no problems with copying. Note we must + if (param != arg) + { + /* Make sure there are no problems with copying. The parameter have a copyable type and the two arguments must have reasonably equivalent types. The latter requirement could be relaxed if we emitted a suitable type conversion statement. */ - && (!is_gimple_reg_type (TREE_TYPE (param)) + if (!is_gimple_reg_type (TREE_TYPE (param)) || !lang_hooks.types_compatible_p (TREE_TYPE (param), - TREE_TYPE (arg)))) - break; + TREE_TYPE (arg))) + break; + + /* The parameter should be a real operand, so that phi node + created for it at the start of the function has the meaning + of copying the value. This test implies is_gimple_reg_type + from the previous condition, however this one could be + relaxed by being more careful with copying the new value + of the parameter (emitting appropriate MODIFY_EXPR and + updating the virtual operands). */ + if (!is_gimple_reg (param)) + break; + } } if (!args && !param) tail_recursion = true; @@ -884,7 +896,11 @@ tree_optimize_tail_calls_1 (bool opt_tailcalls) add_referenced_tmp_var (tmp); phi = create_phi_node (tmp, first); - add_phi_arg (&phi, build_int_cst (ret_type, 0), EDGE_PRED (first, 0)); + add_phi_arg (&phi, + /* RET_TYPE can be a float when -ffast-maths is + enabled. */ + fold_convert (ret_type, integer_zero_node), + EDGE_PRED (first, 0)); a_acc = PHI_RESULT (phi); } @@ -896,7 +912,11 @@ tree_optimize_tail_calls_1 (bool opt_tailcalls) add_referenced_tmp_var (tmp); phi = create_phi_node (tmp, first); - add_phi_arg (&phi, build_int_cst (ret_type, 1), EDGE_PRED (first, 0)); + add_phi_arg (&phi, + /* RET_TYPE can be a float when -ffast-maths is + enabled. */ + fold_convert (ret_type, integer_one_node), + EDGE_PRED (first, 0)); m_acc = PHI_RESULT (phi); } } |