RFC: Should x86-64 support arbitrary calling conventions?

Message ID CAMe9rOp_Pr9RkG-=4ruP1mwVLMM4HJkZAYhr9KAwuQ-4f-TbvA@mail.gmail.com
State New, archived
Headers

Commit Message

H.J. Lu March 24, 2017, 3:26 p.m. UTC
  On Thu, Mar 23, 2017 at 4:14 PM, Richard Henderson <rth@twiddle.net> wrote:
> On 03/24/2017 01:41 AM, H.J. Lu wrote:
>>
>> +# ifdef STATE_SAVE_MASK
>> +       movl $STATE_SAVE_MASK, %eax
>> +       xorl %edx, %edx
>> +       # Clear the XSAVE Header.
>> +       movq $0, (STATE_SAVE_OFFSET + 512)(%rsp)
>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8)(%rsp)
>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8 * 2)(%rsp)
>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8 * 3)(%rsp)
>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8 * 4)(%rsp)
>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8 * 5)(%rsp)
>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8 * 6)(%rsp)
>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8 * 7)(%rsp)
>>  # endif
>
>
> You've just cleared %rdx.  Use that instead of 8*4 bytes of immediate zeros.
>
> Given that you have to ifdef this code into place, isn't it somewhat
> pointless to hide xsave behind a macro in the next line?
>
>> +       STATE_SAVE STATE_SAVE_OFFSET(%rsp)
>
>
> I think it would be clearer to inline the two save instructions instead.
>
>

Good ideas.  Here is the updated patch.
  

Comments

Richard Henderson March 27, 2017, 6:27 a.m. UTC | #1
On 03/25/2017 01:26 AM, H.J. Lu wrote:
> On Thu, Mar 23, 2017 at 4:14 PM, Richard Henderson <rth@twiddle.net> wrote:
>> On 03/24/2017 01:41 AM, H.J. Lu wrote:
>>>
>>> +# ifdef STATE_SAVE_MASK
>>> +       movl $STATE_SAVE_MASK, %eax
>>> +       xorl %edx, %edx
>>> +       # Clear the XSAVE Header.
>>> +       movq $0, (STATE_SAVE_OFFSET + 512)(%rsp)
>>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8)(%rsp)
>>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8 * 2)(%rsp)
>>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8 * 3)(%rsp)
>>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8 * 4)(%rsp)
>>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8 * 5)(%rsp)
>>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8 * 6)(%rsp)
>>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8 * 7)(%rsp)
>>>  # endif
>>
>>
>> You've just cleared %rdx.  Use that instead of 8*4 bytes of immediate zeros.
>>
>> Given that you have to ifdef this code into place, isn't it somewhat
>> pointless to hide xsave behind a macro in the next line?
>>
>>> +       STATE_SAVE STATE_SAVE_OFFSET(%rsp)
>>
>>
>> I think it would be clearer to inline the two save instructions instead.

That said... is there any reason not to use XSAVEC, if supported?

 From the description, it avoids saving components for which XINUSE=0, whereas 
I don't see that same language for XSAVE, even though the XSAVE_BV field would 
still be (un)set for not-in-use components.


r~
  
H.J. Lu March 27, 2017, 3:15 p.m. UTC | #2
On Sun, Mar 26, 2017 at 11:27 PM, Richard Henderson <rth@twiddle.net> wrote:
> On 03/25/2017 01:26 AM, H.J. Lu wrote:
>>
>> On Thu, Mar 23, 2017 at 4:14 PM, Richard Henderson <rth@twiddle.net>
>> wrote:
>>>
>>> On 03/24/2017 01:41 AM, H.J. Lu wrote:
>>>>
>>>>
>>>> +# ifdef STATE_SAVE_MASK
>>>> +       movl $STATE_SAVE_MASK, %eax
>>>> +       xorl %edx, %edx
>>>> +       # Clear the XSAVE Header.
>>>> +       movq $0, (STATE_SAVE_OFFSET + 512)(%rsp)
>>>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8)(%rsp)
>>>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8 * 2)(%rsp)
>>>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8 * 3)(%rsp)
>>>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8 * 4)(%rsp)
>>>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8 * 5)(%rsp)
>>>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8 * 6)(%rsp)
>>>> +       movq $0, (STATE_SAVE_OFFSET + 512 + 8 * 7)(%rsp)
>>>>  # endif
>>>
>>>
>>>
>>> You've just cleared %rdx.  Use that instead of 8*4 bytes of immediate
>>> zeros.
>>>
>>> Given that you have to ifdef this code into place, isn't it somewhat
>>> pointless to hide xsave behind a macro in the next line?
>>>
>>>> +       STATE_SAVE STATE_SAVE_OFFSET(%rsp)
>>>
>>>
>>>
>>> I think it would be clearer to inline the two save instructions instead.
>
>
> That said... is there any reason not to use XSAVEC, if supported?
>
> From the description, it avoids saving components for which XINUSE=0,
> whereas I don't see that same language for XSAVE, even though the XSAVE_BV
> field would still be (un)set for not-in-use components.
>

We can look into XSAVEC after switching to FXSAVE/XSAVE.
  

Patch

From 7542bac3fa3e915c39390e3b7aeb2738ad855278 Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Thu, 23 Mar 2017 08:21:52 -0700
Subject: [PATCH] X86-64: Use fxsave/xsave in _dl_runtime_resolve

In _dl_runtime_resolve, use fxsave/xsave to preserve all vector, mask
and bound registers.  It simplifies _dl_runtime_resolve and supports
different calling conventions.  However, use xsave can be 10X slower
than saving and restoring vector and bound registers individually.
---
 sysdeps/x86/cpu-features-offsets.sym |   1 +
 sysdeps/x86/cpu-features.c           |  26 ++--
 sysdeps/x86/cpu-features.h           |  12 +-
 sysdeps/x86_64/dl-machine.h          |  35 +----
 sysdeps/x86_64/dl-trampoline.S       |  79 +++--------
 sysdeps/x86_64/dl-trampoline.h       | 264 ++++++++++-------------------------
 6 files changed, 119 insertions(+), 298 deletions(-)

diff --git a/sysdeps/x86/cpu-features-offsets.sym b/sysdeps/x86/cpu-features-offsets.sym
index f6739fa..33dd094 100644
--- a/sysdeps/x86/cpu-features-offsets.sym
+++ b/sysdeps/x86/cpu-features-offsets.sym
@@ -15,6 +15,7 @@  CPUID_ECX_OFFSET	offsetof (struct cpuid_registers, ecx)
 CPUID_EDX_OFFSET	offsetof (struct cpuid_registers, edx)
 FAMILY_OFFSET		offsetof (struct cpu_features, family)
 MODEL_OFFSET		offsetof (struct cpu_features, model)
+XSAVE_STATE_SIZE_OFFSET	offsetof (struct cpu_features, xsave_state_size)
 FEATURE_OFFSET		offsetof (struct cpu_features, feature)
 FEATURE_SIZE		sizeof (unsigned int)
 
diff --git a/sysdeps/x86/cpu-features.c b/sysdeps/x86/cpu-features.c
index 33788ed..1b892af 100644
--- a/sysdeps/x86/cpu-features.c
+++ b/sysdeps/x86/cpu-features.c
@@ -93,6 +93,18 @@  get_common_indeces (struct cpu_features *cpu_features,
 		}
 	    }
 	}
+
+      /* For _dl_runtime_resolve, set xsave_state_size to xsave area
+	 size + integer register save size and align it to 64 bytes.  */
+      if (cpu_features->max_cpuid >= 0xd)
+	{
+	  unsigned int eax, ebx, ecx, edx;
+
+	  __cpuid_count (0xd, 0, eax, ebx, ecx, edx);
+	  if (ebx != 0)
+	    cpu_features->xsave_state_size
+	      = (ebx + STATE_SAVE_OFFSET + 63) & -64;
+	}
     }
 }
 
@@ -224,20 +236,6 @@  init_cpu_features (struct cpu_features *cpu_features)
       if (CPU_FEATURES_ARCH_P (cpu_features, AVX2_Usable))
 	cpu_features->feature[index_arch_AVX_Fast_Unaligned_Load]
 	  |= bit_arch_AVX_Fast_Unaligned_Load;
-
-      /* To avoid SSE transition penalty, use _dl_runtime_resolve_slow.
-         If XGETBV suports ECX == 1, use _dl_runtime_resolve_opt.  */
-      cpu_features->feature[index_arch_Use_dl_runtime_resolve_slow]
-	|= bit_arch_Use_dl_runtime_resolve_slow;
-      if (cpu_features->max_cpuid >= 0xd)
-	{
-	  unsigned int eax;
-
-	  __cpuid_count (0xd, 1, eax, ebx, ecx, edx);
-	  if ((eax & (1 << 2)) != 0)
-	    cpu_features->feature[index_arch_Use_dl_runtime_resolve_opt]
-	      |= bit_arch_Use_dl_runtime_resolve_opt;
-	}
     }
   /* This spells out "AuthenticAMD".  */
   else if (ebx == 0x68747541 && ecx == 0x444d4163 && edx == 0x69746e65)
diff --git a/sysdeps/x86/cpu-features.h b/sysdeps/x86/cpu-features.h
index 95f0fcf..f72c0f5 100644
--- a/sysdeps/x86/cpu-features.h
+++ b/sysdeps/x86/cpu-features.h
@@ -37,8 +37,6 @@ 
 #define bit_arch_Prefer_No_VZEROUPPER		(1 << 17)
 #define bit_arch_Fast_Unaligned_Copy		(1 << 18)
 #define bit_arch_Prefer_ERMS			(1 << 19)
-#define bit_arch_Use_dl_runtime_resolve_opt	(1 << 20)
-#define bit_arch_Use_dl_runtime_resolve_slow	(1 << 21)
 
 /* CPUID Feature flags.  */
 
@@ -76,6 +74,11 @@ 
 /* The current maximum size of the feature integer bit array.  */
 #define FEATURE_INDEX_MAX 1
 
+/* Offset for fxsave/xsave area used by _dl_runtime_resolve.  Also need
+   space to preserve RCX, RDX, RSI, RDI, R8, R9 and RAX.  It must be
+   aligned to 16 bytes for fxsave and 64 bytes for xsave.  */
+#define STATE_SAVE_OFFSET (8 * 7 + 8)
+
 #ifdef	__ASSEMBLER__
 
 # include <cpu-features-offsets.h>
@@ -109,8 +112,6 @@ 
 # define index_arch_Prefer_No_VZEROUPPER FEATURE_INDEX_1*FEATURE_SIZE
 # define index_arch_Fast_Unaligned_Copy	FEATURE_INDEX_1*FEATURE_SIZE
 # define index_arch_Prefer_ERMS		FEATURE_INDEX_1*FEATURE_SIZE
-# define index_arch_Use_dl_runtime_resolve_opt FEATURE_INDEX_1*FEATURE_SIZE
-# define index_arch_Use_dl_runtime_resolve_slow FEATURE_INDEX_1*FEATURE_SIZE
 
 
 # if defined (_LIBC) && !IS_IN (nonlib)
@@ -199,6 +200,7 @@  struct cpu_features
   } cpuid[COMMON_CPUID_INDEX_MAX];
   unsigned int family;
   unsigned int model;
+  uintptr_t xsave_state_size;
   unsigned int feature[FEATURE_INDEX_MAX];
 };
 
@@ -281,8 +283,6 @@  extern const struct cpu_features *__get_cpu_features (void)
 # define index_arch_Prefer_No_VZEROUPPER FEATURE_INDEX_1
 # define index_arch_Fast_Unaligned_Copy	FEATURE_INDEX_1
 # define index_arch_Prefer_ERMS		FEATURE_INDEX_1
-# define index_arch_Use_dl_runtime_resolve_opt FEATURE_INDEX_1
-# define index_arch_Use_dl_runtime_resolve_slow FEATURE_INDEX_1
 
 #endif	/* !__ASSEMBLER__ */
 
diff --git a/sysdeps/x86_64/dl-machine.h b/sysdeps/x86_64/dl-machine.h
index daf4d8c..6ff502e 100644
--- a/sysdeps/x86_64/dl-machine.h
+++ b/sysdeps/x86_64/dl-machine.h
@@ -66,12 +66,8 @@  static inline int __attribute__ ((unused, always_inline))
 elf_machine_runtime_setup (struct link_map *l, int lazy, int profile)
 {
   Elf64_Addr *got;
-  extern void _dl_runtime_resolve_sse (ElfW(Word)) attribute_hidden;
-  extern void _dl_runtime_resolve_avx (ElfW(Word)) attribute_hidden;
-  extern void _dl_runtime_resolve_avx_slow (ElfW(Word)) attribute_hidden;
-  extern void _dl_runtime_resolve_avx_opt (ElfW(Word)) attribute_hidden;
-  extern void _dl_runtime_resolve_avx512 (ElfW(Word)) attribute_hidden;
-  extern void _dl_runtime_resolve_avx512_opt (ElfW(Word)) attribute_hidden;
+  extern void _dl_runtime_resolve_fxsave (ElfW(Word)) attribute_hidden;
+  extern void _dl_runtime_resolve_xsave (ElfW(Word)) attribute_hidden;
   extern void _dl_runtime_profile_sse (ElfW(Word)) attribute_hidden;
   extern void _dl_runtime_profile_avx (ElfW(Word)) attribute_hidden;
   extern void _dl_runtime_profile_avx512 (ElfW(Word)) attribute_hidden;
@@ -120,29 +116,10 @@  elf_machine_runtime_setup (struct link_map *l, int lazy, int profile)
 	  /* This function will get called to fix up the GOT entry
 	     indicated by the offset on the stack, and then jump to
 	     the resolved address.  */
-	  if (HAS_ARCH_FEATURE (AVX512F_Usable))
-	    {
-	      if (HAS_ARCH_FEATURE (Use_dl_runtime_resolve_opt))
-		*(ElfW(Addr) *) (got + 2)
-		  = (ElfW(Addr)) &_dl_runtime_resolve_avx512_opt;
-	      else
-		*(ElfW(Addr) *) (got + 2)
-		  = (ElfW(Addr)) &_dl_runtime_resolve_avx512;
-	    }
-	  else if (HAS_ARCH_FEATURE (AVX_Usable))
-	    {
-	      if (HAS_ARCH_FEATURE (Use_dl_runtime_resolve_opt))
-		*(ElfW(Addr) *) (got + 2)
-		  = (ElfW(Addr)) &_dl_runtime_resolve_avx_opt;
-	      else if (HAS_ARCH_FEATURE (Use_dl_runtime_resolve_slow))
-		*(ElfW(Addr) *) (got + 2)
-		  = (ElfW(Addr)) &_dl_runtime_resolve_avx_slow;
-	      else
-		*(ElfW(Addr) *) (got + 2)
-		  = (ElfW(Addr)) &_dl_runtime_resolve_avx;
-	    }
-	  else
-	    *(ElfW(Addr) *) (got + 2) = (ElfW(Addr)) &_dl_runtime_resolve_sse;
+	  *(ElfW(Addr) *) (got + 2)
+	    = (GLRO(dl_x86_cpu_features).xsave_state_size != 0
+	       ? (ElfW(Addr)) &_dl_runtime_resolve_xsave
+	       : (ElfW(Addr)) &_dl_runtime_resolve_fxsave);
 	}
     }
 
diff --git a/sysdeps/x86_64/dl-trampoline.S b/sysdeps/x86_64/dl-trampoline.S
index c14c61a..54dea15 100644
--- a/sysdeps/x86_64/dl-trampoline.S
+++ b/sysdeps/x86_64/dl-trampoline.S
@@ -34,41 +34,24 @@ 
 # define DL_STACK_ALIGNMENT 8
 #endif
 
-#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.  */
+/* True if _dl_runtime_resolve should align stack for STATE_SAVE or align
+   stack to 16 bytes before calling _dl_fixup.  */
 #define DL_RUNTIME_RESOLVE_REALIGN_STACK \
-  (VEC_SIZE > DL_STACK_ALIGNMENT \
-   && VEC_SIZE > DL_RUNTIME_UNALIGNED_VEC_SIZE)
-
-/* Align vector register save area to 16 bytes.  */
-#define REGISTER_SAVE_VEC_OFF	0
+  (STATE_SAVE_ALIGNMENT > DL_STACK_ALIGNMENT \
+   || 16 > DL_STACK_ALIGNMENT)
 
 /* Area on stack to save and restore registers used for parameter
    passing when calling _dl_fixup.  */
 #ifdef __ILP32__
-# define REGISTER_SAVE_RAX	(REGISTER_SAVE_VEC_OFF + VEC_SIZE * 8)
 # define PRESERVE_BND_REGS_PREFIX
 #else
-/* Align bound register save area to 16 bytes.  */
-# define REGISTER_SAVE_BND0	(REGISTER_SAVE_VEC_OFF + VEC_SIZE * 8)
-# define REGISTER_SAVE_BND1	(REGISTER_SAVE_BND0 + 16)
-# define REGISTER_SAVE_BND2	(REGISTER_SAVE_BND1 + 16)
-# define REGISTER_SAVE_BND3	(REGISTER_SAVE_BND2 + 16)
-# define REGISTER_SAVE_RAX	(REGISTER_SAVE_BND3 + 16)
 # ifdef HAVE_MPX_SUPPORT
 #  define PRESERVE_BND_REGS_PREFIX bnd
 # else
 #  define PRESERVE_BND_REGS_PREFIX .byte 0xf2
 # endif
 #endif
+#define REGISTER_SAVE_RAX	0
 #define REGISTER_SAVE_RCX	(REGISTER_SAVE_RAX + 8)
 #define REGISTER_SAVE_RDX	(REGISTER_SAVE_RCX + 8)
 #define REGISTER_SAVE_RSI	(REGISTER_SAVE_RDX + 8)
@@ -80,68 +63,48 @@ 
 
 #define VEC_SIZE		64
 #define VMOVA			vmovdqa64
-#if DL_RUNTIME_RESOLVE_REALIGN_STACK || VEC_SIZE <= DL_STACK_ALIGNMENT
-# define VMOV			vmovdqa64
-#else
-# define VMOV			vmovdqu64
-#endif
 #define VEC(i)			zmm##i
-#define _dl_runtime_resolve	_dl_runtime_resolve_avx512
 #define _dl_runtime_profile	_dl_runtime_profile_avx512
 #include "dl-trampoline.h"
-#undef _dl_runtime_resolve
 #undef _dl_runtime_profile
 #undef VEC
-#undef VMOV
 #undef VMOVA
 #undef VEC_SIZE
 
 #define VEC_SIZE		32
 #define VMOVA			vmovdqa
-#if DL_RUNTIME_RESOLVE_REALIGN_STACK || VEC_SIZE <= DL_STACK_ALIGNMENT
-# define VMOV			vmovdqa
-#else
-# define VMOV			vmovdqu
-#endif
 #define VEC(i)			ymm##i
-#define _dl_runtime_resolve	_dl_runtime_resolve_avx
-#define _dl_runtime_resolve_opt	_dl_runtime_resolve_avx_opt
 #define _dl_runtime_profile	_dl_runtime_profile_avx
 #include "dl-trampoline.h"
-#undef _dl_runtime_resolve
-#undef _dl_runtime_resolve_opt
 #undef _dl_runtime_profile
 #undef VEC
-#undef VMOV
 #undef VMOVA
 #undef VEC_SIZE
 
 /* movaps/movups is 1-byte shorter.  */
 #define VEC_SIZE		16
 #define VMOVA			movaps
-#if DL_RUNTIME_RESOLVE_REALIGN_STACK || VEC_SIZE <= DL_STACK_ALIGNMENT
-# define VMOV			movaps
-#else
-# define VMOV			movups
-#endif
 #define VEC(i)			xmm##i
-#define _dl_runtime_resolve	_dl_runtime_resolve_sse
 #define _dl_runtime_profile	_dl_runtime_profile_sse
 #undef RESTORE_AVX
 #include "dl-trampoline.h"
-#undef _dl_runtime_resolve
 #undef _dl_runtime_profile
-#undef VMOV
+#undef VEC
 #undef VMOVA
+#undef VEC_SIZE
 
-/* Used by _dl_runtime_resolve_avx_opt/_dl_runtime_resolve_avx512_opt
-   to preserve the full vector registers with zero upper bits.  */
-#define VMOVA			vmovdqa
-#if DL_RUNTIME_RESOLVE_REALIGN_STACK || VEC_SIZE <= DL_STACK_ALIGNMENT
-# define VMOV			vmovdqa
-#else
-# define VMOV			vmovdqu
-#endif
-#define _dl_runtime_resolve	_dl_runtime_resolve_sse_vex
-#define _dl_runtime_resolve_opt	_dl_runtime_resolve_avx512_opt
+#define STATE_SAVE_ALIGNMENT	16
+#define _dl_runtime_resolve	_dl_runtime_resolve_fxsave
 #include "dl-trampoline.h"
+#undef _dl_runtime_resolve
+#undef STATE_SAVE_ALIGNMENT
+
+/* Save SSE, AVX, AVX512, mask and bound registers.  */
+#define STATE_SAVE_MASK \
+  ((1 << 1) | (1 << 2) | (1 << 3) | (1 << 5) | (1 << 6) | (1 << 7))
+#define STATE_SAVE_ALIGNMENT	64
+#define _dl_runtime_resolve	_dl_runtime_resolve_xsave
+#include "dl-trampoline.h"
+#undef _dl_runtime_resolve
+#undef STATE_SAVE_MASK
+#undef STATE_SAVE_ALIGNMENT
diff --git a/sysdeps/x86_64/dl-trampoline.h b/sysdeps/x86_64/dl-trampoline.h
index 8db24c1..98b4739 100644
--- a/sysdeps/x86_64/dl-trampoline.h
+++ b/sysdeps/x86_64/dl-trampoline.h
@@ -16,140 +16,47 @@ 
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
-#undef REGISTER_SAVE_AREA_RAW
-#ifdef __ILP32__
-/* X32 saves RCX, RDX, RSI, RDI, R8 and R9 plus RAX as well as VEC0 to
-   VEC7.  */
-# define REGISTER_SAVE_AREA_RAW	(8 * 7 + VEC_SIZE * 8)
-#else
-/* X86-64 saves RCX, RDX, RSI, RDI, R8 and R9 plus RAX as well as
-   BND0, BND1, BND2, BND3 and VEC0 to VEC7. */
-# define REGISTER_SAVE_AREA_RAW	(8 * 7 + 16 * 4 + VEC_SIZE * 8)
-#endif
+	.text
+#ifdef _dl_runtime_resolve
 
-#undef REGISTER_SAVE_AREA
-#undef LOCAL_STORAGE_AREA
-#undef BASE
-#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
-# define BASE			rbx
-# if (REGISTER_SAVE_AREA % VEC_SIZE) != 0
-#  error REGISTER_SAVE_AREA must be multples of VEC_SIZE
-# endif
-#else
-# define REGISTER_SAVE_AREA	REGISTER_SAVE_AREA_RAW
-/* Local stack area before jumping to function address:  All saved
-   registers.  */
-# define LOCAL_STORAGE_AREA	REGISTER_SAVE_AREA
-# define BASE			rsp
-# if (REGISTER_SAVE_AREA % 16) != 8
-#  error REGISTER_SAVE_AREA must be odd multples of 8
+# undef REGISTER_SAVE_AREA
+# undef LOCAL_STORAGE_AREA
+# undef BASE
+
+# if (STATE_SAVE_ALIGNMENT % 16) != 0
+#  error STATE_SAVE_ALIGNMENT must be multples of 16
 # endif
-#endif
 
-	.text
-#ifdef _dl_runtime_resolve_opt
-/* Use the smallest vector registers to preserve the full YMM/ZMM
-   registers to avoid SSE transition penalty.  */
-
-# if VEC_SIZE == 32
-/* Check if the upper 128 bits in %ymm0 - %ymm7 registers are non-zero
-   and preserve %xmm0 - %xmm7 registers with the zero upper bits.  Since
-   there is no SSE transition penalty on AVX512 processors which don't
-   support XGETBV with ECX == 1, _dl_runtime_resolve_avx512_slow isn't
-   provided.   */
-	.globl _dl_runtime_resolve_avx_slow
-	.hidden _dl_runtime_resolve_avx_slow
-	.type _dl_runtime_resolve_avx_slow, @function
-	.align 16
-_dl_runtime_resolve_avx_slow:
-	cfi_startproc
-	cfi_adjust_cfa_offset(16) # Incorporate PLT
-	vorpd %ymm0, %ymm1, %ymm8
-	vorpd %ymm2, %ymm3, %ymm9
-	vorpd %ymm4, %ymm5, %ymm10
-	vorpd %ymm6, %ymm7, %ymm11
-	vorpd %ymm8, %ymm9, %ymm9
-	vorpd %ymm10, %ymm11, %ymm10
-	vpcmpeqd %xmm8, %xmm8, %xmm8
-	vorpd %ymm9, %ymm10, %ymm10
-	vptest %ymm10, %ymm8
-	# Preserve %ymm0 - %ymm7 registers if the upper 128 bits of any
-	# %ymm0 - %ymm7 registers aren't zero.
-	PRESERVE_BND_REGS_PREFIX
-	jnc _dl_runtime_resolve_avx
-	# Use vzeroupper to avoid SSE transition penalty.
-	vzeroupper
-	# Preserve %xmm0 - %xmm7 registers with the zero upper 128 bits
-	# when the upper 128 bits of %ymm0 - %ymm7 registers are zero.
-	PRESERVE_BND_REGS_PREFIX
-	jmp _dl_runtime_resolve_sse_vex
-	cfi_adjust_cfa_offset(-16) # Restore PLT adjustment
-	cfi_endproc
-	.size _dl_runtime_resolve_avx_slow, .-_dl_runtime_resolve_avx_slow
+# if (STATE_SAVE_OFFSET % STATE_SAVE_ALIGNMENT) != 0
+#  error STATE_SAVE_OFFSET must be multples of STATE_SAVE_ALIGNMENT
 # endif
 
-/* Use XGETBV with ECX == 1 to check which bits in vector registers are
-   non-zero and only preserve the non-zero lower bits with zero upper
-   bits.  */
-	.globl _dl_runtime_resolve_opt
-	.hidden _dl_runtime_resolve_opt
-	.type _dl_runtime_resolve_opt, @function
-	.align 16
-_dl_runtime_resolve_opt:
-	cfi_startproc
-	cfi_adjust_cfa_offset(16) # Incorporate PLT
-	pushq %rax
-	cfi_adjust_cfa_offset(8)
-	cfi_rel_offset(%rax, 0)
-	pushq %rcx
-	cfi_adjust_cfa_offset(8)
-	cfi_rel_offset(%rcx, 0)
-	pushq %rdx
-	cfi_adjust_cfa_offset(8)
-	cfi_rel_offset(%rdx, 0)
-	movl $1, %ecx
-	xgetbv
-	movl %eax, %r11d
-	popq %rdx
-	cfi_adjust_cfa_offset(-8)
-	cfi_restore (%rdx)
-	popq %rcx
-	cfi_adjust_cfa_offset(-8)
-	cfi_restore (%rcx)
-	popq %rax
-	cfi_adjust_cfa_offset(-8)
-	cfi_restore (%rax)
-# if VEC_SIZE == 32
-	# For YMM registers, check if YMM state is in use.
-	andl $bit_YMM_state, %r11d
-	# Preserve %xmm0 - %xmm7 registers with the zero upper 128 bits if
-	# YMM state isn't in use.
-	PRESERVE_BND_REGS_PREFIX
-	jz _dl_runtime_resolve_sse_vex
-# elif VEC_SIZE == 16
-	# For ZMM registers, check if YMM state and ZMM state are in
-	# use.
-	andl $(bit_YMM_state | bit_ZMM0_15_state), %r11d
-	cmpl $bit_YMM_state, %r11d
-	# Preserve %zmm0 - %zmm7 registers if ZMM state is in use.
-	PRESERVE_BND_REGS_PREFIX
-	jg _dl_runtime_resolve_avx512
-	# Preserve %ymm0 - %ymm7 registers with the zero upper 256 bits if
-	# ZMM state isn't in use.
-	PRESERVE_BND_REGS_PREFIX
-	je _dl_runtime_resolve_avx
-	# Preserve %xmm0 - %xmm7 registers with the zero upper 384 bits if
-	# neither YMM state nor ZMM state are in use.
+# if DL_RUNTIME_RESOLVE_REALIGN_STACK
+/* Local stack area before jumping to function address: RBX.  */
+#  define LOCAL_STORAGE_AREA	8
+#  define BASE			rbx
+#  ifndef STATE_SAVE_MASK
+/* Use fxsave to save XMM registers.  */
+#   define REGISTER_SAVE_AREA	(512 + STATE_SAVE_OFFSET)
+#   if (REGISTER_SAVE_AREA % 16) != 0
+#    error REGISTER_SAVE_AREA must be multples of 16
+#   endif
+#  endif
 # else
-#  error Unsupported VEC_SIZE!
+#  ifdef STATE_SAVE_MASK
+#   error STATE_SAVE_MASK cannot be defined
+#  endif
+/* Use fxsave to save XMM registers.  */
+#  define REGISTER_SAVE_AREA	(512 + STATE_SAVE_OFFSET + 8)
+/* Local stack area before jumping to function address:  All saved
+   registers.  */
+#  define LOCAL_STORAGE_AREA	REGISTER_SAVE_AREA
+#  define BASE			rsp
+#  if (REGISTER_SAVE_AREA % 16) != 8
+#   error REGISTER_SAVE_AREA must be odd multples of 8
+#  endif
 # endif
-	cfi_adjust_cfa_offset(-16) # Restore PLT adjustment
-	cfi_endproc
-	.size _dl_runtime_resolve_opt, .-_dl_runtime_resolve_opt
-#endif
+
 	.globl _dl_runtime_resolve
 	.hidden _dl_runtime_resolve
 	.type _dl_runtime_resolve, @function
@@ -157,21 +64,29 @@  _dl_runtime_resolve_opt:
 	cfi_startproc
 _dl_runtime_resolve:
 	cfi_adjust_cfa_offset(16) # Incorporate PLT
-#if DL_RUNTIME_RESOLVE_REALIGN_STACK
-# if LOCAL_STORAGE_AREA != 8
-#  error LOCAL_STORAGE_AREA must be 8
-# endif
+# if DL_RUNTIME_RESOLVE_REALIGN_STACK
+#  if LOCAL_STORAGE_AREA != 8
+#   error LOCAL_STORAGE_AREA must be 8
+#  endif
 	pushq %rbx			# push subtracts stack by 8.
 	cfi_adjust_cfa_offset(8)
 	cfi_rel_offset(%rbx, 0)
 	mov %RSP_LP, %RBX_LP
 	cfi_def_cfa_register(%rbx)
-	and $-VEC_SIZE, %RSP_LP
-#endif
+	and $-STATE_SAVE_ALIGNMENT, %RSP_LP
+# endif
+# ifdef REGISTER_SAVE_AREA
 	sub $REGISTER_SAVE_AREA, %RSP_LP
-#if !DL_RUNTIME_RESOLVE_REALIGN_STACK
+#  if !DL_RUNTIME_RESOLVE_REALIGN_STACK
 	cfi_adjust_cfa_offset(REGISTER_SAVE_AREA)
-#endif
+#  endif
+# else
+#  if IS_IN (rtld)
+	sub _rtld_local_ro+RTLD_GLOBAL_RO_DL_X86_CPU_FEATURES_OFFSET+XSAVE_STATE_SIZE_OFFSET(%rip), %RSP_LP
+#  else
+	sub _dl_x86_cpu_features+XSAVE_STATE_SIZE_OFFSET(%rip), %RSP_LP
+#  endif
+# endif
 	# Preserve registers otherwise clobbered.
 	movq %rax, REGISTER_SAVE_RAX(%rsp)
 	movq %rcx, REGISTER_SAVE_RCX(%rsp)
@@ -180,59 +95,36 @@  _dl_runtime_resolve:
 	movq %rdi, REGISTER_SAVE_RDI(%rsp)
 	movq %r8, REGISTER_SAVE_R8(%rsp)
 	movq %r9, REGISTER_SAVE_R9(%rsp)
-	VMOV %VEC(0), (REGISTER_SAVE_VEC_OFF)(%rsp)
-	VMOV %VEC(1), (REGISTER_SAVE_VEC_OFF + VEC_SIZE)(%rsp)
-	VMOV %VEC(2), (REGISTER_SAVE_VEC_OFF + VEC_SIZE * 2)(%rsp)
-	VMOV %VEC(3), (REGISTER_SAVE_VEC_OFF + VEC_SIZE * 3)(%rsp)
-	VMOV %VEC(4), (REGISTER_SAVE_VEC_OFF + VEC_SIZE * 4)(%rsp)
-	VMOV %VEC(5), (REGISTER_SAVE_VEC_OFF + VEC_SIZE * 5)(%rsp)
-	VMOV %VEC(6), (REGISTER_SAVE_VEC_OFF + VEC_SIZE * 6)(%rsp)
-	VMOV %VEC(7), (REGISTER_SAVE_VEC_OFF + VEC_SIZE * 7)(%rsp)
-#ifndef __ILP32__
-	# We also have to preserve bound registers.  These are nops if
-	# Intel MPX isn't available or disabled.
-# ifdef HAVE_MPX_SUPPORT
-	bndmov %bnd0, REGISTER_SAVE_BND0(%rsp)
-	bndmov %bnd1, REGISTER_SAVE_BND1(%rsp)
-	bndmov %bnd2, REGISTER_SAVE_BND2(%rsp)
-	bndmov %bnd3, REGISTER_SAVE_BND3(%rsp)
+# ifdef STATE_SAVE_MASK
+	movl $STATE_SAVE_MASK, %eax
+	xorl %edx, %edx
+	# Clear the XSAVE Header.
+	movq %rdx, (STATE_SAVE_OFFSET + 512)(%rsp)
+	movq %rdx, (STATE_SAVE_OFFSET + 512 + 8)(%rsp)
+	movq %rdx, (STATE_SAVE_OFFSET + 512 + 8 * 2)(%rsp)
+	movq %rdx, (STATE_SAVE_OFFSET + 512 + 8 * 3)(%rsp)
+	movq %rdx, (STATE_SAVE_OFFSET + 512 + 8 * 4)(%rsp)
+	movq %rdx, (STATE_SAVE_OFFSET + 512 + 8 * 5)(%rsp)
+	movq %rdx, (STATE_SAVE_OFFSET + 512 + 8 * 6)(%rsp)
+	movq %rdx, (STATE_SAVE_OFFSET + 512 + 8 * 7)(%rsp)
+	xsave STATE_SAVE_OFFSET(%rsp)
 # else
-#  if REGISTER_SAVE_BND0 == 0
-	.byte 0x66,0x0f,0x1b,0x04,0x24
-#  else
-	.byte 0x66,0x0f,0x1b,0x44,0x24,REGISTER_SAVE_BND0
-#  endif
-	.byte 0x66,0x0f,0x1b,0x4c,0x24,REGISTER_SAVE_BND1
-	.byte 0x66,0x0f,0x1b,0x54,0x24,REGISTER_SAVE_BND2
-	.byte 0x66,0x0f,0x1b,0x5c,0x24,REGISTER_SAVE_BND3
+	fxsave STATE_SAVE_OFFSET(%rsp)
 # endif
-#endif
 	# Copy args pushed by PLT in register.
 	# %rdi: link_map, %rsi: reloc_index
 	mov (LOCAL_STORAGE_AREA + 8)(%BASE), %RSI_LP
 	mov LOCAL_STORAGE_AREA(%BASE), %RDI_LP
 	call _dl_fixup		# Call resolver.
 	mov %RAX_LP, %R11_LP	# Save return value
-#ifndef __ILP32__
-	# Restore bound registers.  These are nops if Intel MPX isn't
-	# avaiable or disabled.
-# ifdef HAVE_MPX_SUPPORT
-	bndmov REGISTER_SAVE_BND3(%rsp), %bnd3
-	bndmov REGISTER_SAVE_BND2(%rsp), %bnd2
-	bndmov REGISTER_SAVE_BND1(%rsp), %bnd1
-	bndmov REGISTER_SAVE_BND0(%rsp), %bnd0
+	# Get register content back.
+# ifdef STATE_SAVE_MASK
+	movl $STATE_SAVE_MASK, %eax
+	xorl %edx, %edx
+	xrstor STATE_SAVE_OFFSET(%rsp)
 # else
-	.byte 0x66,0x0f,0x1a,0x5c,0x24,REGISTER_SAVE_BND3
-	.byte 0x66,0x0f,0x1a,0x54,0x24,REGISTER_SAVE_BND2
-	.byte 0x66,0x0f,0x1a,0x4c,0x24,REGISTER_SAVE_BND1
-#  if REGISTER_SAVE_BND0 == 0
-	.byte 0x66,0x0f,0x1a,0x04,0x24
-#  else
-	.byte 0x66,0x0f,0x1a,0x44,0x24,REGISTER_SAVE_BND0
-#  endif
+	fxrstor STATE_SAVE_OFFSET(%rsp)
 # endif
-#endif
-	# Get register content back.
 	movq REGISTER_SAVE_R9(%rsp), %r9
 	movq REGISTER_SAVE_R8(%rsp), %r8
 	movq REGISTER_SAVE_RDI(%rsp), %rdi
@@ -240,20 +132,12 @@  _dl_runtime_resolve:
 	movq REGISTER_SAVE_RDX(%rsp), %rdx
 	movq REGISTER_SAVE_RCX(%rsp), %rcx
 	movq REGISTER_SAVE_RAX(%rsp), %rax
-	VMOV (REGISTER_SAVE_VEC_OFF)(%rsp), %VEC(0)
-	VMOV (REGISTER_SAVE_VEC_OFF + VEC_SIZE)(%rsp), %VEC(1)
-	VMOV (REGISTER_SAVE_VEC_OFF + VEC_SIZE * 2)(%rsp), %VEC(2)
-	VMOV (REGISTER_SAVE_VEC_OFF + VEC_SIZE * 3)(%rsp), %VEC(3)
-	VMOV (REGISTER_SAVE_VEC_OFF + VEC_SIZE * 4)(%rsp), %VEC(4)
-	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_RUNTIME_RESOLVE_REALIGN_STACK
+# if DL_RUNTIME_RESOLVE_REALIGN_STACK
 	mov %RBX_LP, %RSP_LP
 	cfi_def_cfa_register(%rsp)
 	movq (%rsp), %rbx
 	cfi_restore(%rbx)
-#endif
+# endif
 	# Adjust stack(PLT did 2 pushes)
 	add $(LOCAL_STORAGE_AREA + 16), %RSP_LP
 	cfi_adjust_cfa_offset(-(LOCAL_STORAGE_AREA + 16))
@@ -262,11 +146,9 @@  _dl_runtime_resolve:
 	jmp *%r11		# Jump to function address.
 	cfi_endproc
 	.size _dl_runtime_resolve, .-_dl_runtime_resolve
+#endif
 
 
-/* To preserve %xmm0 - %xmm7 registers, dl-trampoline.h is included
-   twice, for _dl_runtime_resolve_sse and _dl_runtime_resolve_sse_vex.
-   But we don't need another _dl_runtime_profile for XMM registers.  */
 #if !defined PROF && defined _dl_runtime_profile
 # if (LR_VECTOR_OFFSET % VEC_SIZE) != 0
 #  error LR_VECTOR_OFFSET must be multples of VEC_SIZE
-- 
2.9.3