[PATCH v1 1/2] x86: Move mem{p}{mov|cpy}_{chk_}erms to its own file
Noah Goldstein
goldstein.w.n@gmail.com
Tue Jun 28 15:27:56 GMT 2022
The primary memmove_{impl}_unaligned_erms implementations don't
interact with this function. Putting them in same file both
wastes space and unnecessarily bloats a hot code section.
---
sysdeps/x86_64/multiarch/memmove-erms.S | 53 +++++++++++++++++++
.../multiarch/memmove-vec-unaligned-erms.S | 50 -----------------
2 files changed, 53 insertions(+), 50 deletions(-)
create mode 100644 sysdeps/x86_64/multiarch/memmove-erms.S
diff --git a/sysdeps/x86_64/multiarch/memmove-erms.S b/sysdeps/x86_64/multiarch/memmove-erms.S
new file mode 100644
index 0000000000..d98d21644b
--- /dev/null
+++ b/sysdeps/x86_64/multiarch/memmove-erms.S
@@ -0,0 +1,53 @@
+#include <sysdep.h>
+
+#if defined USE_MULTIARCH && IS_IN (libc)
+ .text
+ENTRY (__mempcpy_chk_erms)
+ cmp %RDX_LP, %RCX_LP
+ jb HIDDEN_JUMPTARGET (__chk_fail)
+END (__mempcpy_chk_erms)
+
+/* Only used to measure performance of REP MOVSB. */
+ENTRY (__mempcpy_erms)
+ mov %RDI_LP, %RAX_LP
+ /* Skip zero length. */
+ test %RDX_LP, %RDX_LP
+ jz 2f
+ add %RDX_LP, %RAX_LP
+ jmp L(start_movsb)
+END (__mempcpy_erms)
+
+ENTRY (__memmove_chk_erms)
+ cmp %RDX_LP, %RCX_LP
+ jb HIDDEN_JUMPTARGET (__chk_fail)
+END (__memmove_chk_erms)
+
+ENTRY (__memmove_erms)
+ movq %rdi, %rax
+ /* Skip zero length. */
+ test %RDX_LP, %RDX_LP
+ jz 2f
+L(start_movsb):
+ mov %RDX_LP, %RCX_LP
+ cmp %RSI_LP, %RDI_LP
+ jb 1f
+ /* Source == destination is less common. */
+ je 2f
+ lea (%rsi,%rcx), %RDX_LP
+ cmp %RDX_LP, %RDI_LP
+ jb L(movsb_backward)
+1:
+ rep movsb
+2:
+ ret
+L(movsb_backward):
+ leaq -1(%rdi,%rcx), %rdi
+ leaq -1(%rsi,%rcx), %rsi
+ std
+ rep movsb
+ cld
+ ret
+END (__memmove_erms)
+strong_alias (__memmove_erms, __memcpy_erms)
+strong_alias (__memmove_chk_erms, __memcpy_chk_erms)
+#endif
diff --git a/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S b/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S
index d1518b8bab..04747133b7 100644
--- a/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S
+++ b/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S
@@ -239,56 +239,6 @@ L(start):
#endif
#if defined USE_MULTIARCH && IS_IN (libc)
END (MEMMOVE_SYMBOL (__memmove, unaligned))
-# if VEC_SIZE == 16
-ENTRY (__mempcpy_chk_erms)
- cmp %RDX_LP, %RCX_LP
- jb HIDDEN_JUMPTARGET (__chk_fail)
-END (__mempcpy_chk_erms)
-
-/* Only used to measure performance of REP MOVSB. */
-ENTRY (__mempcpy_erms)
- mov %RDI_LP, %RAX_LP
- /* Skip zero length. */
- test %RDX_LP, %RDX_LP
- jz 2f
- add %RDX_LP, %RAX_LP
- jmp L(start_movsb)
-END (__mempcpy_erms)
-
-ENTRY (__memmove_chk_erms)
- cmp %RDX_LP, %RCX_LP
- jb HIDDEN_JUMPTARGET (__chk_fail)
-END (__memmove_chk_erms)
-
-ENTRY (__memmove_erms)
- movq %rdi, %rax
- /* Skip zero length. */
- test %RDX_LP, %RDX_LP
- jz 2f
-L(start_movsb):
- mov %RDX_LP, %RCX_LP
- cmp %RSI_LP, %RDI_LP
- jb 1f
- /* Source == destination is less common. */
- je 2f
- lea (%rsi,%rcx), %RDX_LP
- cmp %RDX_LP, %RDI_LP
- jb L(movsb_backward)
-1:
- rep movsb
-2:
- ret
-L(movsb_backward):
- leaq -1(%rdi,%rcx), %rdi
- leaq -1(%rsi,%rcx), %rsi
- std
- rep movsb
- cld
- ret
-END (__memmove_erms)
-strong_alias (__memmove_erms, __memcpy_erms)
-strong_alias (__memmove_chk_erms, __memcpy_chk_erms)
-# endif
# ifdef SHARED
ENTRY (MEMMOVE_CHK_SYMBOL (__mempcpy_chk, unaligned_erms))
--
2.34.1
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