On 2022/05/27 12:00, Takayuki 'January June' Suwa via Gcc-patches wrote:
On 2022/05/27 1:57, Max Filippov wrote:
is that something that can be addressed in this patch?
seems hard to resolve, because the RTL-generation pass passes only 68
bytes in that case:
the culprit is here, but i don't know whether it is known regression or not.
diff --git a/gcc/expr.cc b/gcc/expr.cc
index 7197996cec7..be100dd9946 100644
--- a/gcc/expr.cc
+++ b/gcc/expr.cc
@@ -6043,13 +6043,19 @@ store_expr (tree exp, rtx target, int call_param_p,
if (!can_store_by_pieces (str_copy_len, string_cst_read_str,
(void *) str, MEM_ALIGN (target), false))
goto normal_expr;
-
- dest_mem = store_by_pieces (target, str_copy_len,
string_cst_read_str,
- (void *) str, MEM_ALIGN (target), false,
- RETURN_END);
- clear_storage (adjust_address_1 (dest_mem, BLKmode, 0, 1, 1, 0,
- exp_len - str_copy_len),
- GEN_INT (exp_len - str_copy_len), BLOCK_OP_NORMAL);
+ if (TREE_STRING_LENGTH (str) == 1 && *TREE_STRING_POINTER (str) == 0)
+ clear_storage (adjust_address_1 (target, BLKmode, 0, 1, 1, 0,
+ exp_len),
+ GEN_INT (exp_len), BLOCK_OP_NORMAL);
+ else
+ {
+ dest_mem = store_by_pieces (target, str_copy_len, string_cst_read_str,
+ (void *) str, MEM_ALIGN (target), false,
+ RETURN_END);
+ clear_storage (adjust_address_1 (dest_mem, BLKmode, 0, 1, 1, 0,
+ exp_len - str_copy_len),
+ GEN_INT (exp_len - str_copy_len), BLOCK_OP_NORMAL);
+ }
return NULL_RTX;
}
else
