[PATCH v3 03/13] Rewrite abi-note.S in C.
Szabolcs Nagy
szabolcs.nagy@arm.com
Fri May 15 14:40:47 GMT 2020
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 --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>
--
2.17.1
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