[x86_64] Set DL_RUNTIME_UNALIGNED_VEC_SIZE to 8

Due to GCC bug:

   https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58066

__tls_get_addr may be called with 8-byte stack alignment.  Although
this bug has been fixed in GCC 4.9.4, 5.3 and 6, we can't assume
that stack will be always aligned at 16 bytes.  Since SSE optimized
memory/string functions with aligned SSE register load and store are
used in the dynamic linker, we must set DL_RUNTIME_UNALIGNED_VEC_SIZE
to 8 so that _dl_runtime_resolve_sse will align the stack before
calling _dl_fixup:

Dump of assembler code for function _dl_runtime_resolve_sse:
   0x00007ffff7deea90 <+0>:	push   %rbx
   0x00007ffff7deea91 <+1>:	mov    %rsp,%rbx
   0x00007ffff7deea94 <+4>:	and    $0xfffffffffffffff0,%rsp
                                ^^^^^^^^^^^ Align stack to 16 bytes
   0x00007ffff7deea98 <+8>:	sub    $0x100,%rsp
   0x00007ffff7deea9f <+15>:	mov    %rax,0xc0(%rsp)
   0x00007ffff7deeaa7 <+23>:	mov    %rcx,0xc8(%rsp)
   0x00007ffff7deeaaf <+31>:	mov    %rdx,0xd0(%rsp)
   0x00007ffff7deeab7 <+39>:	mov    %rsi,0xd8(%rsp)
   0x00007ffff7deeabf <+47>:	mov    %rdi,0xe0(%rsp)
   0x00007ffff7deeac7 <+55>:	mov    %r8,0xe8(%rsp)
   0x00007ffff7deeacf <+63>:	mov    %r9,0xf0(%rsp)
   0x00007ffff7deead7 <+71>:	movaps %xmm0,(%rsp)
   0x00007ffff7deeadb <+75>:	movaps %xmm1,0x10(%rsp)
   0x00007ffff7deeae0 <+80>:	movaps %xmm2,0x20(%rsp)
   0x00007ffff7deeae5 <+85>:	movaps %xmm3,0x30(%rsp)
   0x00007ffff7deeaea <+90>:	movaps %xmm4,0x40(%rsp)
   0x00007ffff7deeaef <+95>:	movaps %xmm5,0x50(%rsp)
   0x00007ffff7deeaf4 <+100>:	movaps %xmm6,0x60(%rsp)
   0x00007ffff7deeaf9 <+105>:	movaps %xmm7,0x70(%rsp)

	[BZ #19679]
	* sysdeps/x86_64/dl-trampoline.S (DL_RUNIME_UNALIGNED_VEC_SIZE):
	Renamed to ...
	(DL_RUNTIME_UNALIGNED_VEC_SIZE): This.  Set to 8.
	(DL_RUNIME_RESOLVE_REALIGN_STACK): Renamed to ...
	(DL_RUNTIME_RESOLVE_REALIGN_STACK): This.  Updated.
	(DL_RUNIME_RESOLVE_REALIGN_STACK): Renamed to ...
	(DL_RUNTIME_RESOLVE_REALIGN_STACK): This.
	* sysdeps/x86_64/dl-trampoline.h
	(DL_RUNIME_RESOLVE_REALIGN_STACK): Renamed to ...
	(DL_RUNTIME_RESOLVE_REALIGN_STACK): This.

diff --git a/ChangeLog b/ChangeLog
index 1ed0e7b70e7f196abe766f6e60f9e8a600b8a0bb..db05bdc0eb1f0176f684d772df3cdba996809f91 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,17 @@
+2016-02-19  H.J. Lu  <hongjiu.lu@intel.com>
+
+       [BZ #19679]
+       * sysdeps/x86_64/dl-trampoline.S (DL_RUNIME_UNALIGNED_VEC_SIZE):
+       Renamed to ...
+       (DL_RUNTIME_UNALIGNED_VEC_SIZE): This.  Set to 8.
+       (DL_RUNIME_RESOLVE_REALIGN_STACK): Renamed to ...
+       (DL_RUNTIME_RESOLVE_REALIGN_STACK): This.  Updated.
+       (DL_RUNIME_RESOLVE_REALIGN_STACK): Renamed to ...
+       (DL_RUNTIME_RESOLVE_REALIGN_STACK): This.
+       * sysdeps/x86_64/dl-trampoline.h
+       (DL_RUNIME_RESOLVE_REALIGN_STACK): Renamed to ...
+       (DL_RUNTIME_RESOLVE_REALIGN_STACK): This.
+
 2016-02-19  Mark Wielaard  <mjw@redhat.com>
 
        * elf/elf.h: Add NT_ARM_SYSTEM_CALL.

diff --git a/sysdeps/x86_64/dl-trampoline.S b/sysdeps/x86_64/dl-trampoline.S
index 9fb6b13983b20cd0ad7909b7814ba7b45add8604..39b8771aa79d669dcf15b7475a621023ce59d340 100644 (file)
--- a/sysdeps/x86_64/dl-trampoline.S
+++ b/sysdeps/x86_64/dl-trampoline.S
@@ -33,15 +33,19 @@
 # define DL_STACK_ALIGNMENT 8
 #endif
 
-#ifndef DL_RUNIME_UNALIGNED_VEC_SIZE
-/* The maximum size of unaligned vector load and store.  */
-# define DL_RUNIME_UNALIGNED_VEC_SIZE 16
+#ifndef DL_RUNTIME_UNALIGNED_VEC_SIZE
+/* The maximum size in bytes of unaligned vector load and store in the
+   dynamic linker.  Since SSE optimized memory/string functions with
+   aligned SSE register load and store are used in the dynamic linker,
+   we must set this to 8 so that _dl_runtime_resolve_sse will align the
+   stack before calling _dl_fixup.  */
+# define DL_RUNTIME_UNALIGNED_VEC_SIZE 8
 #endif
 
 /* True if _dl_runtime_resolve should align stack to VEC_SIZE bytes.  */
-#define DL_RUNIME_RESOLVE_REALIGN_STACK \
+#define DL_RUNTIME_RESOLVE_REALIGN_STACK \
   (VEC_SIZE > DL_STACK_ALIGNMENT \
-   && VEC_SIZE > DL_RUNIME_UNALIGNED_VEC_SIZE)
+   && VEC_SIZE > DL_RUNTIME_UNALIGNED_VEC_SIZE)
 
 /* Align vector register save area to 16 bytes.  */
 #define REGISTER_SAVE_VEC_OFF  0
@@ -76,7 +80,7 @@
 #ifdef HAVE_AVX512_ASM_SUPPORT
 # define VEC_SIZE              64
 # define VMOVA                 vmovdqa64
-# if DL_RUNIME_RESOLVE_REALIGN_STACK || VEC_SIZE <= DL_STACK_ALIGNMENT
+# if DL_RUNTIME_RESOLVE_REALIGN_STACK || VEC_SIZE <= DL_STACK_ALIGNMENT
 #  define VMOV                 vmovdqa64
 # else
 #  define VMOV                 vmovdqu64
@@ -100,7 +104,7 @@ strong_alias (_dl_runtime_profile_avx, _dl_runtime_profile_avx512)
 
 #define VEC_SIZE               32
 #define VMOVA                  vmovdqa
-#if DL_RUNIME_RESOLVE_REALIGN_STACK || VEC_SIZE <= DL_STACK_ALIGNMENT
+#if DL_RUNTIME_RESOLVE_REALIGN_STACK || VEC_SIZE <= DL_STACK_ALIGNMENT
 # define VMOV                  vmovdqa
 #else
 # define VMOV                  vmovdqu
@@ -119,7 +123,7 @@ strong_alias (_dl_runtime_profile_avx, _dl_runtime_profile_avx512)
 /* movaps/movups is 1-byte shorter.  */
 #define VEC_SIZE               16
 #define VMOVA                  movaps
-#if DL_RUNIME_RESOLVE_REALIGN_STACK || VEC_SIZE <= DL_STACK_ALIGNMENT
+#if DL_RUNTIME_RESOLVE_REALIGN_STACK || VEC_SIZE <= DL_STACK_ALIGNMENT
 # define VMOV                  movaps
 #else
 # define VMOV                  movups

diff --git a/sysdeps/x86_64/dl-trampoline.h b/sysdeps/x86_64/dl-trampoline.h
index f4191833abfd89d4ad956c7b0257a97f733902ca..b90836ab137faf13266c641cf34cbd4f087687bb 100644 (file)
--- a/sysdeps/x86_64/dl-trampoline.h
+++ b/sysdeps/x86_64/dl-trampoline.h
@@ -30,7 +30,7 @@
 #undef REGISTER_SAVE_AREA
 #undef LOCAL_STORAGE_AREA
 #undef BASE
-#if DL_RUNIME_RESOLVE_REALIGN_STACK
+#if DL_RUNTIME_RESOLVE_REALIGN_STACK
 # define REGISTER_SAVE_AREA    (REGISTER_SAVE_AREA_RAW + 8)
 /* Local stack area before jumping to function address: RBX.  */
 # define LOCAL_STORAGE_AREA    8
@@ -57,7 +57,7 @@
        cfi_startproc
 _dl_runtime_resolve:
        cfi_adjust_cfa_offset(16) # Incorporate PLT
-#if DL_RUNIME_RESOLVE_REALIGN_STACK
+#if DL_RUNTIME_RESOLVE_REALIGN_STACK
 # if LOCAL_STORAGE_AREA != 8
 #  error LOCAL_STORAGE_AREA must be 8
 # endif
@@ -146,7 +146,7 @@ _dl_runtime_resolve:
        VMOV (REGISTER_SAVE_VEC_OFF + VEC_SIZE * 5)(%rsp), %VEC(5)
        VMOV (REGISTER_SAVE_VEC_OFF + VEC_SIZE * 6)(%rsp), %VEC(6)
        VMOV (REGISTER_SAVE_VEC_OFF + VEC_SIZE * 7)(%rsp), %VEC(7)
-#if DL_RUNIME_RESOLVE_REALIGN_STACK
+#if DL_RUNTIME_RESOLVE_REALIGN_STACK
        mov %RBX_LP, %RSP_LP
        cfi_def_cfa_register(%rsp)
        movq (%rsp), %rbx