This is the mail archive of the libc-alpha@sourceware.org mailing list for the glibc project.

Index Nav:	[Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav:	[Date Prev] [Date Next]	[Thread Prev] [Thread Next]
Other format:	[Raw text]

[PATCH 05/27] [AARCH64] Use PTR_REG in crti.S.

From: Yury Norov <ynorov at caviumnetworks dot com>
To: <libc-alpha at sourceware dot org>, <linux-kernel at vger dot kernel dot org>
Cc: <arnd at arndb dot de>, <catalin dot marinas at arm dot com>, <marcus dot shawcroft at arm dot com>, <philb at gnu dot org>, <davem at davemloft dot net>, <szabolcs dot nagy at arm dot com>, <maxim dot kuvyrkov at linaro dot org>, <joseph at codesourcery dot com>, <pinskia at gmail dot com>, Andrew Pinski <apinski at cavium dot com>, Yury Norov <ynorov at caviumnetworks dot com>
Date: Tue, 21 Jun 2016 08:06:49 +0300
Subject: [PATCH 05/27] [AARCH64] Use PTR_REG in crti.S.
Authentication-results: sourceware.org; auth=none
Authentication-results: spf=none (sender IP is ) smtp dot mailfrom=Yuri dot Norov at caviumnetworks dot com;
References: <1466485631-3532-1-git-send-email-ynorov at caviumnetworks dot com>
Spamdiagnosticmetadata: NSPM
Spamdiagnosticoutput: 1:99

From: Andrew Pinski <apinski@cavium.com>

call_weak_fn loads from a pointer, so use PTR_REG so the load
is 32bits for ILP32.

* sysdeps/aarch64/crti.S: Include sysdep.h
(call_weak_fn): Use PTR_REG when loading from
PREINIT_FUNCTION.

AARCH64: Make RTLD_START paramatizable

Make RTLD_START paramatizable for ILP32 and LP64 usage and provides common
code between ILP32.

* sysdeps/aarch64/dl-machine.h (RTLD_START): Rename to ...
(RTLD_START_1): This and add PTR, PTR_SIZE_LOG, and PTR_SP arguments.
(RTLD_START): New macro which uses RTLD_START_1.

Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
---
 sysdeps/aarch64/crti.S       |   3 +-
 sysdeps/aarch64/dl-machine.h | 128 ++++++++++++++++++++++---------------------
 2 files changed, 69 insertions(+), 62 deletions(-)

diff --git a/sysdeps/aarch64/crti.S b/sysdeps/aarch64/crti.S
index 53ccb42..6e149b5 100644
--- a/sysdeps/aarch64/crti.S
+++ b/sysdeps/aarch64/crti.S
@@ -39,6 +39,7 @@
    they can be called as functions.  The symbols _init and _fini are
    magic and cause the linker to emit DT_INIT and DT_FINI.  */
 
+#include <sysdep.h>
 #include <libc-symbols.h>
 
 #ifndef PREINIT_FUNCTION
@@ -60,7 +61,7 @@
 	.type	call_weak_fn, %function
 call_weak_fn:
 	adrp	x0, :got:PREINIT_FUNCTION
-	ldr	x0, [x0, #:got_lo12:PREINIT_FUNCTION]
+	ldr	PTR_REG(0), [x0, #:got_lo12:PREINIT_FUNCTION]
 	cbz	x0, 1f
 	b	PREINIT_FUNCTION
 1:
diff --git a/sysdeps/aarch64/dl-machine.h b/sysdeps/aarch64/dl-machine.h
index a16cb11..7a49852 100644
--- a/sysdeps/aarch64/dl-machine.h
+++ b/sysdeps/aarch64/dl-machine.h
@@ -126,68 +126,74 @@ elf_machine_runtime_setup (struct link_map *l, int lazy, int profile)
 /* Initial entry point for the dynamic linker. The C function
    _dl_start is the real entry point, its return value is the user
    program's entry point */
+#ifdef __LP64__
+#define RTLD_START RTLD_START_1("x", "3", "sp")
+#else
+#define RTLD_START RTLD_START_1("w", "2", "wsp")
+#endif
+
 
-#define RTLD_START asm ("\
-.text								\n\
-.globl _start							\n\
-.type _start, %function						\n\
-.globl _dl_start_user						\n\
-.type _dl_start_user, %function					\n\
-_start:								\n\
-	mov	x0,	sp					\n\
-	bl	_dl_start					\n\
-	// returns user entry point in x0			\n\
-	mov	x21, x0						\n\
-_dl_start_user:							\n\
-	// get the original arg count				\n\
-	ldr	x1, [sp]					\n\
-	// get the argv address					\n\
-	add	x2, sp, #8					\n\
-	// get _dl_skip_args to see if we were			\n\
-	// invoked as an executable				\n\
-	adrp	x4, _dl_skip_args				\n\
-        ldr	w4, [x4, #:lo12:_dl_skip_args]			\n\
-	// do we need to adjust argc/argv			\n\
-        cmp	w4, 0						\n\
-	beq	.L_done_stack_adjust				\n\
-	// subtract _dl_skip_args from original arg count	\n\
-	sub	x1, x1, x4					\n\
-	// store adjusted argc back to stack			\n\
-	str	x1, [sp]					\n\
-	// find the first unskipped argument			\n\
-	mov	x3, x2						\n\
-	add	x4, x2, x4, lsl #3				\n\
-	// shuffle argv down					\n\
-1:	ldr	x5, [x4], #8					\n\
-	str	x5, [x3], #8					\n\
-	cmp	x5, #0						\n\
-	bne	1b						\n\
-	// shuffle envp down					\n\
-1:	ldr	x5, [x4], #8					\n\
-	str	x5, [x3], #8					\n\
-	cmp	x5, #0						\n\
-	bne	1b						\n\
-	// shuffle auxv down					\n\
-1:	ldp	x0, x5, [x4, #16]!				\n\
-	stp	x0, x5, [x3], #16				\n\
-	cmp	x0, #0						\n\
-	bne	1b						\n\
-	// Update _dl_argv					\n\
-	adrp	x3, _dl_argv					\n\
-	str	x2, [x3, #:lo12:_dl_argv]			\n\
-.L_done_stack_adjust:						\n\
-	// compute envp						\n\
-	add	x3, x2, x1, lsl #3				\n\
-	add	x3, x3, #8					\n\
-	adrp	x16, _rtld_local				\n\
-        add	x16, x16, #:lo12:_rtld_local			\n\
-        ldr	x0, [x16]					\n\
-	bl	_dl_init					\n\
-	// load the finalizer function				\n\
-	adrp	x0, _dl_fini					\n\
-	add	x0, x0, #:lo12:_dl_fini				\n\
-	// jump to the user_s entry point			\n\
-	br      x21						\n\
+#define RTLD_START_1(PTR, PTR_SIZE_LOG, PTR_SP) asm ("\
+.text									\n\
+.globl _start								\n\
+.type _start, %function							\n\
+.globl _dl_start_user							\n\
+.type _dl_start_user, %function						\n\
+_start:									\n\
+	mov	" PTR "0, " PTR_SP "					\n\
+	bl	_dl_start						\n\
+	// returns user entry point in x0				\n\
+	mov	x21, x0							\n\
+_dl_start_user:								\n\
+	// get the original arg count					\n\
+	ldr	" PTR "1, [sp]						\n\
+	// get the argv address						\n\
+	add	" PTR "2, " PTR_SP ", #(1<<"  PTR_SIZE_LOG ")		\n\
+	// get _dl_skip_args to see if we were				\n\
+	// invoked as an executable					\n\
+	adrp	x4, _dl_skip_args					\n\
+        ldr	w4, [x4, #:lo12:_dl_skip_args]				\n\
+	// do we need to adjust argc/argv				\n\
+        cmp	w4, 0							\n\
+	beq	.L_done_stack_adjust					\n\
+	// subtract _dl_skip_args from original arg count		\n\
+	sub	" PTR "1, " PTR "1, " PTR "4				\n\
+	// store adjusted argc back to stack				\n\
+	str	" PTR "1, [sp]						\n\
+	// find the first unskipped argument				\n\
+	mov	" PTR "3, " PTR "2					\n\
+	add	" PTR "4, " PTR "2, " PTR "4, lsl #" PTR_SIZE_LOG "	\n\
+	// shuffle argv down						\n\
+1:	ldr	" PTR "5, [x4], #(1<<"  PTR_SIZE_LOG ")			\n\
+	str	" PTR "5, [x3], #(1<<"  PTR_SIZE_LOG ")			\n\
+	cmp	" PTR "5, #0						\n\
+	bne	1b							\n\
+	// shuffle envp down						\n\
+1:	ldr	" PTR "5, [x4], #(1<<"  PTR_SIZE_LOG ")			\n\
+	str	" PTR "5, [x3], #(1<<"  PTR_SIZE_LOG ")			\n\
+	cmp	" PTR "5, #0						\n\
+	bne	1b							\n\
+	// shuffle auxv down						\n\
+1:	ldp	" PTR "0, " PTR "5, [x4, #(2<<"  PTR_SIZE_LOG ")]!	\n\
+	stp	" PTR "0, " PTR "5, [x3], #(2<<"  PTR_SIZE_LOG ")	\n\
+	cmp	" PTR "0, #0						\n\
+	bne	1b							\n\
+	// Update _dl_argv						\n\
+	adrp	x3, _dl_argv						\n\
+	str	" PTR "2, [x3, #:lo12:_dl_argv]				\n\
+.L_done_stack_adjust:							\n\
+	// compute envp							\n\
+	add	" PTR "3, " PTR "2, " PTR "1, lsl #" PTR_SIZE_LOG "	\n\
+	add	" PTR "3, " PTR "3, #(1<<"  PTR_SIZE_LOG ")		\n\
+	adrp	x16, _rtld_local					\n\
+        add	" PTR "16, " PTR "16, #:lo12:_rtld_local		\n\
+        ldr	" PTR "0, [x16]						\n\
+	bl	_dl_init						\n\
+	// load the finalizer function					\n\
+	adrp	x0, _dl_fini						\n\
+	add	" PTR "0, " PTR "0, #:lo12:_dl_fini			\n\
+	// jump to the user_s entry point				\n\
+	br      x21							\n\
 ");
 
 #define elf_machine_type_class(type)					\
-- 
2.7.4

Follow-Ups:
- Re: [PATCH 05/27] [AARCH64] Use PTR_REG in crti.S.
  - From: Joseph Myers

References:
- [RFC PATCH 00/27] ARM64: support ILP32
  - From: Yury Norov

Index Nav:	[Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav:	[Date Prev] [Date Next]	[Thread Prev] [Thread Next]