diff mbox series

[v2,03/13] Rewrite abi-note.S in C.

Message ID 91817a2bc76bf8315125322ee866f99b256fe867.1589277641.git.szabolcs.nagy@arm.com
State New
Headers show
Series aarch64: branch protection support | expand

Commit Message

Szabolcs Nagy May 12, 2020, 10:14 a.m. UTC 
Using C code allows the compiler to add target specific object file
markings based on CFLAGS.

The arm specific abi-note.S is removed and similar object file fix
up will be avoided on AArch64 with standard branch-prtection.
---
 csu/{abi-note.S => abi-note.c} | 28 ++++++++++++++++++----------
 sysdeps/arm/abi-note.S         |  8 --------
 2 files changed, 18 insertions(+), 18 deletions(-)
 rename csu/{abi-note.S => abi-note.c} (88%)
 delete mode 100644 sysdeps/arm/abi-note.S
diff mbox series

Patch

diff --git a/csu/abi-note.S b/csu/abi-note.c
similarity index 88%
rename from csu/abi-note.S
rename to csu/abi-note.c
index 2b4b5f8824..cd45f17345 100644
--- a/csu/abi-note.S
+++ b/csu/abi-note.c
@@ -53,6 +53,7 @@  offset	length	contents
    identify the earliest release of that OS that supports this ABI.
    See abi-tags (top level) for details. */
 
+#include <stdint.h>
 #include <config.h>
 #include <abi-tag.h>		/* OS-specific ABI tag value */
 
@@ -60,13 +61,20 @@  offset	length	contents
    name begins with `.note' and creates a PT_NOTE program header entry
    pointing at it. */
 
-	.section ".note.ABI-tag", "a"
-	.p2align 2
-	.long 1f - 0f		/* name length */
-	.long 3f - 2f		/* data length */
-	.long  1		/* note type */
-0:	.asciz "GNU"		/* vendor name */
-1:	.p2align 2
-2:	.long __ABI_TAG_OS	/* note data: the ABI tag */
-	.long __ABI_TAG_VERSION
-3:	.p2align 2		/* pad out section */
+/* Note: Custom type is used as ElfW(Nhdr) is wrong on 64 bit targets.  */
+
+__attribute__ ((used, aligned (4), section (".note.ABI-tag")))
+static const struct
+{
+  int32_t namesz;
+  int32_t descsz;
+  int32_t type;
+  char name[4];
+  int32_t desc[4];
+} __abi_tag = {
+  4,
+  16,
+  1,
+  "GNU",
+  { __ABI_TAG_OS, __ABI_TAG_VERSION }
+};
diff --git a/sysdeps/arm/abi-note.S b/sysdeps/arm/abi-note.S
deleted file mode 100644
index 07bd4c4619..0000000000
--- a/sysdeps/arm/abi-note.S
+++ /dev/null
@@ -1,8 +0,0 @@ 
-/* Tag_ABI_align8_preserved: This code preserves 8-byte
-   alignment in any callee.  */
-	.eabi_attribute 25, 1
-/* Tag_ABI_align8_needed: This code may require 8-byte alignment from
-   the caller.  */
-	.eabi_attribute 24, 1
-
-#include <csu/abi-note.S>