diff options
| -rw-r--r-- | gcc/expr.c | 34 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.target/i386/pr95052.c | 20 |
2 files changed, 53 insertions, 1 deletions
@@ -5583,6 +5583,7 @@ store_expr (tree exp, rtx target, int call_param_p, rtx temp; rtx alt_rtl = NULL_RTX; location_t loc = curr_insn_location (); + bool shortened_string_cst = false; if (VOID_TYPE_P (TREE_TYPE (exp))) { @@ -5749,7 +5750,32 @@ store_expr (tree exp, rtx target, int call_param_p, /* If we want to use a nontemporal or a reverse order store, force the value into a register first. */ tmp_target = nontemporal || reverse ? NULL_RTX : target; - temp = expand_expr_real (exp, tmp_target, GET_MODE (target), + tree rexp = exp; + if (TREE_CODE (exp) == STRING_CST + && tmp_target == target + && GET_MODE (target) == BLKmode + && TYPE_MODE (TREE_TYPE (exp)) == BLKmode) + { + rtx size = expr_size (exp); + if (CONST_INT_P (size) + && size != const0_rtx + && (UINTVAL (size) + > ((unsigned HOST_WIDE_INT) TREE_STRING_LENGTH (exp) + 32))) + { + /* If the STRING_CST has much larger array type than + TREE_STRING_LENGTH, only emit the TREE_STRING_LENGTH part of + it into the rodata section as the code later on will use + memset zero for the remainder anyway. See PR95052. */ + tmp_target = NULL_RTX; + rexp = copy_node (exp); + tree index + = build_index_type (size_int (TREE_STRING_LENGTH (exp) - 1)); + TREE_TYPE (rexp) = build_array_type (TREE_TYPE (TREE_TYPE (exp)), + index); + shortened_string_cst = true; + } + } + temp = expand_expr_real (rexp, tmp_target, GET_MODE (target), (call_param_p ? EXPAND_STACK_PARM : EXPAND_NORMAL), &alt_rtl, false); @@ -5763,6 +5789,7 @@ store_expr (tree exp, rtx target, int call_param_p, && TREE_CODE (exp) != ERROR_MARK && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp))) { + gcc_assert (!shortened_string_cst); if (GET_MODE_CLASS (GET_MODE (target)) != GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (exp))) && known_eq (GET_MODE_BITSIZE (GET_MODE (target)), @@ -5815,6 +5842,7 @@ store_expr (tree exp, rtx target, int call_param_p, { if (GET_MODE (temp) != GET_MODE (target) && GET_MODE (temp) != VOIDmode) { + gcc_assert (!shortened_string_cst); if (GET_MODE (target) == BLKmode) { /* Handle calls that return BLKmode values in registers. */ @@ -5900,6 +5928,8 @@ store_expr (tree exp, rtx target, int call_param_p, emit_label (label); } } + else if (shortened_string_cst) + gcc_unreachable (); /* Handle calls that return values in multiple non-contiguous locations. The Irix 6 ABI has examples of this. */ else if (GET_CODE (target) == PARALLEL) @@ -5929,6 +5959,8 @@ store_expr (tree exp, rtx target, int call_param_p, emit_move_insn (target, temp); } } + else + gcc_assert (!shortened_string_cst); return NULL_RTX; } diff --git a/gcc/testsuite/gcc.target/i386/pr95052.c b/gcc/testsuite/gcc.target/i386/pr95052.c new file mode 100644 index 0000000..1bbfd7e --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/pr95052.c @@ -0,0 +1,20 @@ +/* PR middle-end/95052 */ +/* { dg-do compile } */ +/* { dg-options "-Os -mtune=skylake" } */ +/* Verify we don't waste almost 2 megabytes of .rodata. */ +/* { dg-final { scan-assembler-not "\.zero\t1048\[0-9]\[0-9]\[0-9]" } } */ +extern void foo (char *, unsigned); + +int +main () +{ + char str[1024 * 1024] = + "fooiuhluhpiuhliuhliyfyukyfklyugkiuhpoipoipoipoipoipoipoipoipoipoipoipoipoimipoipiuhoulouihnliuhl"; + char arr[1024 * 1024] = + { 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 6, 2, 3, + 4, 5, 6, 7, 8, 9, 0, 3, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, + 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0 }; + foo (str, sizeof (str)); + foo (arr, sizeof (arr)); + return 0; +} |