On 08/29/2017 09:09 AM, Joerg Sonnenberger wrote:
> On Mon, Aug 28, 2017 at 11:42:53AM -0600, Jeff Law wrote:
>> Does the attached (untested) patch work for you?
>
> Works for the cases I care about, yes.
Thanks. Here's what I'm committing after the usual bootstrap &
regression testing cycle on x86. This includes a regression test for
the testsuite.
Jeff
commit 371072bf395be11f36ef31bb3cfec06bbfc58597
Author: law <law@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Fri Sep 1 16:26:00 2017 +0000
* varasm.c (bss_initializer_p): Do not put constants into .bss
(categorize_decl_for_section): Handle bss_initializer_p returning
false when DECL_INITIAL is NULL.
* gcc.target/i386/const-in-bss.c: New test.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@251602
138bc75d-0d04-0410-961f-82ee72b054a4
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index e71380e5c9d..f9d9eb74a3a 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2017-09-01 Joerg Sonnenberger <[email protected]>
+ Jeff Law <[email protected]>
+
+ * varasm.c (bss_initializer_p): Do not put constants into .bss
+ (categorize_decl_for_section): Handle bss_initializer_p returning
+ false when DECL_INITIAL is NULL.
+
2017-09-01 Andreas Krebbel <[email protected]>
PR target/82012
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index fe6e4301bff..e82751438d6 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -5,6 +5,8 @@
2017-09-01 Jeff Law <[email protected]>
+ * gcc.target/i386/const-in-bss.c: New test.
+
PR tree-optimization/82052
* gcc.c-torture/compile/pr82052.c: New test.
diff --git a/gcc/testsuite/gcc.target/i386/const-in-bss.c
b/gcc/testsuite/gcc.target/i386/const-in-bss.c
new file mode 100644
index 00000000000..c70aa0bcb4e
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/const-in-bss.c
@@ -0,0 +1,6 @@
+/* { dg-do compile { target *-*-linux* } } */
+
+__attribute__((section("readonly1"))) const int foo1c;
+
+/* { dg-final { scan-assembler "readonly1,\"a\"" } } */
+/* { dg-final { scan-assembler-not "readonly1,\"aw\"" } } */
diff --git a/gcc/varasm.c b/gcc/varasm.c
index e5393377a43..d38d2c2721b 100644
--- a/gcc/varasm.c
+++ b/gcc/varasm.c
@@ -976,16 +976,16 @@ decode_reg_name (const char *name)
bool
bss_initializer_p (const_tree decl)
{
- return (DECL_INITIAL (decl) == NULL
- /* In LTO we have no errors in program; error_mark_node is used
- to mark offlined constructors. */
- || (DECL_INITIAL (decl) == error_mark_node
- && !in_lto_p)
- || (flag_zero_initialized_in_bss
- /* Leave constant zeroes in .rodata so they
- can be shared. */
- && !TREE_READONLY (decl)
- && initializer_zerop (DECL_INITIAL (decl))));
+ /* Do not put constants into the .bss section, they belong in a readonly
+ section. */
+ return (!TREE_READONLY (decl)
+ && (DECL_INITIAL (decl) == NULL
+ /* In LTO we have no errors in program; error_mark_node is used
+ to mark offlined constructors. */
+ || (DECL_INITIAL (decl) == error_mark_node
+ && !in_lto_p)
+ || (flag_zero_initialized_in_bss
+ && initializer_zerop (DECL_INITIAL (decl)))));
}
/* Compute the alignment of variable specified by DECL.
@@ -6517,7 +6517,8 @@ categorize_decl_for_section (const_tree decl, int reloc)
ret = SECCAT_BSS;
else if (! TREE_READONLY (decl)
|| TREE_SIDE_EFFECTS (decl)
- || ! TREE_CONSTANT (DECL_INITIAL (decl)))
+ || (DECL_INITIAL (decl)
+ && ! TREE_CONSTANT (DECL_INITIAL (decl))))
{
/* Here the reloc_rw_mask is not testing whether the section should
be read-only or not, but whether the dynamic link will have to
@@ -6537,7 +6538,8 @@ categorize_decl_for_section (const_tree decl, int reloc)
location. -fmerge-all-constants allows even that (at the
expense of not conforming). */
ret = SECCAT_RODATA;
- else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
+ else if (DECL_INITIAL (decl)
+ && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
ret = SECCAT_RODATA_MERGE_STR_INIT;
else
ret = SECCAT_RODATA_MERGE_CONST;
