Backport from Hongjiu Lu <hongjiu.lu@intel.com> of these upstream
commits:
commit b52b0d793dcb226ecb0ecca1e672ca265973233c
Author: H.J. Lu <hjl.tools@gmail.com>
Date: Fri Oct 20 11:00:08 2017 -0700
x86-64: Use fxsave/xsave/xsavec in _dl_runtime_resolve [BZ #21265]
In _dl_runtime_resolve, use fxsave/xsave/xsavec to preserve all vector,
mask and bound registers. It simplifies _dl_runtime_resolve and supports
different calling conventions. ld.so code size is reduced by more than
1 KB. However, use fxsave/xsave/xsavec takes a little bit more cycles
than saving and restoring vector and bound registers individually.
Latency for _dl_runtime_resolve to lookup the function, foo, from one
shared library plus libc.so:
Before After Change
Westmere (SSE)/fxsave 345 866 151%
IvyBridge (AVX)/xsave 420 643 53%
Haswell (AVX)/xsave 713 1252 75%
Skylake (AVX+MPX)/xsavec 559 719 28%
Skylake (AVX512+MPX)/xsavec 145 272 87%
Ryzen (AVX)/xsavec 280 553 97%
This is the worst case where portion of time spent for saving and
restoring registers is bigger than majority of cases. With smaller
_dl_runtime_resolve code size, overall performance impact is negligible.
On IvyBridge, differences in build and test time of binutils with lazy
binding GCC and binutils are noises. On Westmere, differences in
bootstrap and "makc check" time of GCC 7 with lazy binding GCC and
binutils are also noises.
commit 0ac8ee53e8efbfd6e1c37094b4653f5c2dad65b5
Author: H.J. Lu <hjl.tools@gmail.com>
Date: Fri Aug 26 08:57:42 2016 -0700
X86-64: Correct CFA in _dl_runtime_resolve
When stack is re-aligned in _dl_runtime_resolve, there is no need to
adjust CFA when allocating register save area on stack.
* sysdeps/x86_64/dl-trampoline.h (_dl_runtime_resolve): Don't
adjust CFA when allocating register save area on re-aligned
stack.
Storing the full xsave state size in xsave_state_full_size was not needed
because RHEL7 does not have the full tunables support that would use this,
therefore support for xsave_state_full_size has been removed from the
changes in b52b0d793dcb226ecb0ecca1e672ca265973233c
diff --git a/sysdeps/x86/cpu-features-offsets.sym b/sysdeps/x86/cpu-features-offsets.sym
index a9d53d195f9eb609..1415005fc22be806 100644
--- a/sysdeps/x86/cpu-features-offsets.sym
+++ b/sysdeps/x86/cpu-features-offsets.sym
@@ -5,3 +5,5 @@
#define rtld_global_ro_offsetof(mem) offsetof (struct rtld_global_ro, mem)
RTLD_GLOBAL_RO_DL_X86_CPU_FEATURES_OFFSET rtld_global_ro_offsetof (_dl_x86_cpu_features)
+
+XSAVE_STATE_SIZE_OFFSET offsetof (struct cpu_features, xsave_state_size)
diff --git a/sysdeps/x86/cpu-features.c b/sysdeps/x86/cpu-features.c
index 17e9835f5716ca12..c9bb4fa6f524ba4e 100644
--- a/sysdeps/x86/cpu-features.c
+++ b/sysdeps/x86/cpu-features.c
@@ -18,6 +18,7 @@
#include <cpuid.h>
#include <cpu-features.h>
+#include <libc-internal.h>
static inline void
get_common_indeces (struct cpu_features *cpu_features,
@@ -148,20 +149,6 @@ init_cpu_features (struct cpu_features *cpu_features)
break;
}
}
-
- /* To avoid SSE transition penalty, use _dl_runtime_resolve_slow.
- If XGETBV suports ECX == 1, use _dl_runtime_resolve_opt. */
- cpu_features->feature[index_Use_dl_runtime_resolve_slow]
- |= bit_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_Use_dl_runtime_resolve_opt]
- |= bit_Use_dl_runtime_resolve_opt;
- }
}
/* This spells out "AuthenticAMD". */
else if (ebx == 0x68747541 && ecx == 0x444d4163 && edx == 0x69746e65)
@@ -243,6 +230,71 @@ init_cpu_features (struct cpu_features *cpu_features)
/* Determine if FMA4 is usable. */
if (HAS_CPU_FEATURE (FMA4))
cpu_features->feature[index_FMA4_Usable] |= bit_FMA4_Usable;
+
+ /* 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
+ = ALIGN_UP (ebx + STATE_SAVE_OFFSET, 64);
+
+ __cpuid_count (0xd, 1, eax, ebx, ecx, edx);
+
+ /* Check if XSAVEC is available. */
+ if ((eax & (1 << 1)) != 0)
+ {
+ unsigned int xstate_comp_offsets[32];
+ unsigned int xstate_comp_sizes[32];
+ unsigned int i;
+
+ xstate_comp_offsets[0] = 0;
+ xstate_comp_offsets[1] = 160;
+ xstate_comp_offsets[2] = 576;
+ xstate_comp_sizes[0] = 160;
+ xstate_comp_sizes[1] = 256;
+
+ for (i = 2; i < 32; i++)
+ {
+ if ((STATE_SAVE_MASK & (1 << i)) != 0)
+ {
+ __cpuid_count (0xd, i, eax, ebx, ecx, edx);
+ xstate_comp_sizes[i] = eax;
+ }
+ else
+ {
+ ecx = 0;
+ xstate_comp_sizes[i] = 0;
+ }
+
+ if (i > 2)
+ {
+ xstate_comp_offsets[i]
+ = (xstate_comp_offsets[i - 1]
+ + xstate_comp_sizes[i -1]);
+ if ((ecx & (1 << 1)) != 0)
+ xstate_comp_offsets[i]
+ = ALIGN_UP (xstate_comp_offsets[i], 64);
+ }
+ }
+
+ /* Use XSAVEC. */
+ unsigned int size
+ = xstate_comp_offsets[31] + xstate_comp_sizes[31];
+ if (size)
+ {
+ cpu_features->xsave_state_size
+ = ALIGN_UP (size + STATE_SAVE_OFFSET, 64);
+ cpu_features->feature[index_XSAVEC_Usable]
+ |= bit_XSAVEC_Usable;
+ }
+ }
+ }
+ }
}
}
diff --git a/sysdeps/x86/cpu-features.h b/sysdeps/x86/cpu-features.h
index c69abb349af8f09c..4e2e6fabb39ab600 100644
--- a/sysdeps/x86/cpu-features.h
+++ b/sysdeps/x86/cpu-features.h
@@ -34,8 +34,7 @@
#define bit_AVX512DQ_Usable (1 << 13)
#define bit_Prefer_MAP_32BIT_EXEC (1 << 16)
#define bit_Prefer_No_VZEROUPPER (1 << 17)
-#define bit_Use_dl_runtime_resolve_opt (1 << 20)
-#define bit_Use_dl_runtime_resolve_slow (1 << 21)
+#define bit_XSAVEC_Usable (1 << 18)
/* CPUID Feature flags. */
@@ -70,10 +69,20 @@
/* 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)
+
+/* Save SSE, AVX, AVX512, mask and bound registers. */
+#define STATE_SAVE_MASK \
+ ((1 << 1) | (1 << 2) | (1 << 3) | (1 << 5) | (1 << 6) | (1 << 7))
+
#ifdef __ASSEMBLER__
# include <ifunc-defines.h>
# include <rtld-global-offsets.h>
+# include <cpu-features-offsets.h>
# define index_SSE2 COMMON_CPUID_INDEX_1*CPUID_SIZE+CPUID_EDX_OFFSET
# define index_SSSE3 COMMON_CPUID_INDEX_1*CPUID_SIZE+CPUID_ECX_OFFSET
@@ -98,8 +107,6 @@
# define index_AVX512DQ_Usable FEATURE_INDEX_1*FEATURE_SIZE
# define index_Prefer_MAP_32BIT_EXEC FEATURE_INDEX_1*FEATURE_SIZE
# define index_Prefer_No_VZEROUPPER FEATURE_INDEX_1*FEATURE_SIZE
-# define index_Use_dl_runtime_resolve_opt FEATURE_INDEX_1*FEATURE_SIZE
-# define index_Use_dl_runtime_resolve_slow FEATURE_INDEX_1*FEATURE_SIZE
# if defined (_LIBC) && !IS_IN (nonlib)
@@ -214,6 +221,12 @@ struct cpu_features
} cpuid[COMMON_CPUID_INDEX_MAX];
unsigned int family;
unsigned int model;
+ /* The type must be unsigned long int so that we use
+
+ sub xsave_state_size_offset(%rip) %RSP_LP
+
+ in _dl_runtime_resolve. */
+ unsigned long int xsave_state_size;
unsigned int feature[FEATURE_INDEX_MAX];
};
@@ -279,8 +292,7 @@ extern const struct cpu_features *__get_cpu_features (void)
# define index_AVX512DQ_Usable FEATURE_INDEX_1
# define index_Prefer_MAP_32BIT_EXEC FEATURE_INDEX_1
# define index_Prefer_No_VZEROUPPER FEATURE_INDEX_1
-# define index_Use_dl_runtime_resolve_opt FEATURE_INDEX_1
-# define index_Use_dl_runtime_resolve_slow FEATURE_INDEX_1
+# define index_XSAVEC_Usable FEATURE_INDEX_1
#endif /* !__ASSEMBLER__ */
diff --git a/sysdeps/x86_64/dl-machine.h b/sysdeps/x86_64/dl-machine.h
index 2a4cda1aff57db98..da89f2a6174a0d94 100644
--- a/sysdeps/x86_64/dl-machine.h
+++ b/sysdeps/x86_64/dl-machine.h
@@ -66,12 +66,9 @@ 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_resolve_xsavec (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 +117,14 @@ 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;
- }
+ if (GLRO(dl_x86_cpu_features).xsave_state_size != 0)
+ *(ElfW(Addr) *) (got + 2)
+ = (HAS_ARCH_FEATURE (XSAVEC_Usable)
+ ? (ElfW(Addr)) &_dl_runtime_resolve_xsavec
+ : (ElfW(Addr)) &_dl_runtime_resolve_xsave);
else
- *(ElfW(Addr) *) (got + 2) = (ElfW(Addr)) &_dl_runtime_resolve_sse;
+ *(ElfW(Addr) *) (got + 2)
+ = (ElfW(Addr)) &_dl_runtime_resolve_fxsave;
}
}
diff --git a/sysdeps/x86_64/dl-trampoline.S b/sysdeps/x86_64/dl-trampoline.S
index bd2d72edfea406e5..215a314f06ca874c 100644
--- a/sysdeps/x86_64/dl-trampoline.S
+++ b/sysdeps/x86_64/dl-trampoline.S
@@ -34,37 +34,24 @@
# 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
-#endif
-
-/* True if _dl_runtime_resolve should align stack to VEC_SIZE bytes. */
-#define DL_RUNIME_RESOLVE_REALIGN_STACK \
- (VEC_SIZE > DL_STACK_ALIGNMENT \
- && VEC_SIZE > DL_RUNIME_UNALIGNED_VEC_SIZE)
-
-/* Align vector register save area to 16 bytes. */
-#define REGISTER_SAVE_VEC_OFF 0
+/* 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 \
+ (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)
@@ -72,71 +59,60 @@
#define REGISTER_SAVE_R8 (REGISTER_SAVE_RDI + 8)
#define REGISTER_SAVE_R9 (REGISTER_SAVE_R8 + 8)
+#define RESTORE_AVX
+
#define VEC_SIZE 64
#define VMOVA vmovdqa64
-#if DL_RUNIME_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
-#define RESTORE_AVX
#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_RUNIME_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_RUNIME_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 USE_FXSAVE
+#define STATE_SAVE_ALIGNMENT 16
+#define _dl_runtime_resolve _dl_runtime_resolve_fxsave
#include "dl-trampoline.h"
+#undef _dl_runtime_resolve
+#undef USE_FXSAVE
+#undef STATE_SAVE_ALIGNMENT
+
+#define USE_XSAVE
+#define STATE_SAVE_ALIGNMENT 64
+#define _dl_runtime_resolve _dl_runtime_resolve_xsave
+#include "dl-trampoline.h"
+#undef _dl_runtime_resolve
+#undef USE_XSAVE
+#undef STATE_SAVE_ALIGNMENT
+
+#define USE_XSAVEC
+#define STATE_SAVE_ALIGNMENT 64
+#define _dl_runtime_resolve _dl_runtime_resolve_xsavec
+#include "dl-trampoline.h"
+#undef _dl_runtime_resolve
+#undef USE_XSAVEC
+#undef STATE_SAVE_ALIGNMENT
diff --git a/sysdeps/x86_64/dl-trampoline.h b/sysdeps/x86_64/dl-trampoline.h
index 849cab4cd30e122a..525de575e3c4e52c 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_RUNIME_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
+# ifdef USE_FXSAVE
+/* 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!
+# ifndef USE_FXSAVE
+# error USE_FXSAVE must 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
@@ -157,19 +64,30 @@ _dl_runtime_resolve_opt:
cfi_startproc
_dl_runtime_resolve:
cfi_adjust_cfa_offset(16) # Incorporate PLT
-#if DL_RUNIME_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
cfi_adjust_cfa_offset(REGISTER_SAVE_AREA)
+# endif
+# else
+ # Allocate stack space of the required size to save the state.
+# 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)
@@ -178,59 +96,48 @@ _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 USE_FXSAVE
+ fxsave STATE_SAVE_OFFSET(%rsp)
# else
-# if REGISTER_SAVE_BND0 == 0
- .byte 0x66,0x0f,0x1b,0x04,0x24
+ movl $STATE_SAVE_MASK, %eax
+ xorl %edx, %edx
+ # Clear the XSAVE Header.
+# ifdef USE_XSAVE
+ movq %rdx, (STATE_SAVE_OFFSET + 512)(%rsp)
+ movq %rdx, (STATE_SAVE_OFFSET + 512 + 8)(%rsp)
+# endif
+ 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)
+# ifdef USE_XSAVE
+ xsave STATE_SAVE_OFFSET(%rsp)
# else
- .byte 0x66,0x0f,0x1b,0x44,0x24,REGISTER_SAVE_BND0
+ # Since glibc 2.23 requires only binutils 2.22 or later, xsavec
+ # may not be supported. Use .byte directive instead.
+# if STATE_SAVE_OFFSET != 0x40
+# error STATE_SAVE_OFFSET != 0x40
+# endif
+ # xsavec STATE_SAVE_OFFSET(%rsp)
+ .byte 0x0f, 0xc7, 0x64, 0x24, 0x40
# 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
# 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 USE_FXSAVE
+ fxrstor 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
+ movl $STATE_SAVE_MASK, %eax
+ xorl %edx, %edx
+ xrstor 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
@@ -238,20 +145,12 @@ _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_RUNIME_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))
@@ -260,11 +159,9 @@ _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