460 lines
14 KiB
Diff
460 lines
14 KiB
Diff
From b62ace2740a106222e124cc86956448fa07abf4d Mon Sep 17 00:00:00 2001
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From: Noah Goldstein <goldstein.w.n@gmail.com>
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Date: Sun, 6 Feb 2022 00:54:18 -0600
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Subject: [PATCH] x86: Improve vec generation in memset-vec-unaligned-erms.S
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Content-type: text/plain; charset=UTF-8
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No bug.
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Split vec generation into multiple steps. This allows the
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broadcast in AVX2 to use 'xmm' registers for the L(less_vec)
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case. This saves an expensive lane-cross instruction and removes
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the need for 'vzeroupper'.
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For SSE2 replace 2x 'punpck' instructions with zero-idiom 'pxor' for
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byte broadcast.
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Results for memset-avx2 small (geomean of N = 20 benchset runs).
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size, New Time, Old Time, New / Old
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0, 4.100, 3.831, 0.934
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1, 5.074, 4.399, 0.867
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2, 4.433, 4.411, 0.995
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4, 4.487, 4.415, 0.984
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8, 4.454, 4.396, 0.987
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16, 4.502, 4.443, 0.987
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All relevant string/wcsmbs tests are passing.
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Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
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---
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sysdeps/x86_64/memset.S | 21 ++-
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.../multiarch/memset-avx2-unaligned-erms.S | 18 +-
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.../multiarch/memset-avx512-unaligned-erms.S | 18 +-
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.../multiarch/memset-evex-unaligned-erms.S | 18 +-
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.../multiarch/memset-vec-unaligned-erms.S | 164 +++++++++++-------
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5 files changed, 152 insertions(+), 87 deletions(-)
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diff --git a/sysdeps/x86_64/memset.S b/sysdeps/x86_64/memset.S
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index 8672b030..27debd2b 100644
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--- a/sysdeps/x86_64/memset.S
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+++ b/sysdeps/x86_64/memset.S
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@@ -28,17 +28,22 @@
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#define VMOVU movups
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#define VMOVA movaps
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-#define MEMSET_VDUP_TO_VEC0_AND_SET_RETURN(d, r) \
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+# define MEMSET_SET_VEC0_AND_SET_RETURN(d, r) \
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movd d, %xmm0; \
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- movq r, %rax; \
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- punpcklbw %xmm0, %xmm0; \
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- punpcklwd %xmm0, %xmm0; \
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- pshufd $0, %xmm0, %xmm0
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+ pxor %xmm1, %xmm1; \
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+ pshufb %xmm1, %xmm0; \
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+ movq r, %rax
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-#define WMEMSET_VDUP_TO_VEC0_AND_SET_RETURN(d, r) \
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+# define WMEMSET_SET_VEC0_AND_SET_RETURN(d, r) \
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movd d, %xmm0; \
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- movq r, %rax; \
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- pshufd $0, %xmm0, %xmm0
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+ pshufd $0, %xmm0, %xmm0; \
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+ movq r, %rax
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+
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+# define MEMSET_VDUP_TO_VEC0_HIGH()
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+# define MEMSET_VDUP_TO_VEC0_LOW()
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+
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+# define WMEMSET_VDUP_TO_VEC0_HIGH()
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+# define WMEMSET_VDUP_TO_VEC0_LOW()
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#define SECTION(p) p
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diff --git a/sysdeps/x86_64/multiarch/memset-avx2-unaligned-erms.S b/sysdeps/x86_64/multiarch/memset-avx2-unaligned-erms.S
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index 1af668af..c0bf2875 100644
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--- a/sysdeps/x86_64/multiarch/memset-avx2-unaligned-erms.S
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+++ b/sysdeps/x86_64/multiarch/memset-avx2-unaligned-erms.S
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@@ -10,15 +10,18 @@
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# define VMOVU vmovdqu
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# define VMOVA vmovdqa
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-# define MEMSET_VDUP_TO_VEC0_AND_SET_RETURN(d, r) \
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+# define MEMSET_SET_VEC0_AND_SET_RETURN(d, r) \
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vmovd d, %xmm0; \
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- movq r, %rax; \
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- vpbroadcastb %xmm0, %ymm0
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+ movq r, %rax;
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-# define WMEMSET_VDUP_TO_VEC0_AND_SET_RETURN(d, r) \
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- vmovd d, %xmm0; \
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- movq r, %rax; \
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- vpbroadcastd %xmm0, %ymm0
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+# define WMEMSET_SET_VEC0_AND_SET_RETURN(d, r) \
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+ MEMSET_SET_VEC0_AND_SET_RETURN(d, r)
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+
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+# define MEMSET_VDUP_TO_VEC0_HIGH() vpbroadcastb %xmm0, %ymm0
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+# define MEMSET_VDUP_TO_VEC0_LOW() vpbroadcastb %xmm0, %xmm0
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+
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+# define WMEMSET_VDUP_TO_VEC0_HIGH() vpbroadcastd %xmm0, %ymm0
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+# define WMEMSET_VDUP_TO_VEC0_LOW() vpbroadcastd %xmm0, %xmm0
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# ifndef SECTION
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# define SECTION(p) p##.avx
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@@ -30,5 +33,6 @@
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# define WMEMSET_SYMBOL(p,s) p##_avx2_##s
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# endif
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+# define USE_XMM_LESS_VEC
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# include "memset-vec-unaligned-erms.S"
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#endif
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diff --git a/sysdeps/x86_64/multiarch/memset-avx512-unaligned-erms.S b/sysdeps/x86_64/multiarch/memset-avx512-unaligned-erms.S
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index f14d6f84..5241216a 100644
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--- a/sysdeps/x86_64/multiarch/memset-avx512-unaligned-erms.S
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+++ b/sysdeps/x86_64/multiarch/memset-avx512-unaligned-erms.S
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@@ -15,13 +15,19 @@
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# define VZEROUPPER
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-# define MEMSET_VDUP_TO_VEC0_AND_SET_RETURN(d, r) \
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- movq r, %rax; \
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- vpbroadcastb d, %VEC0
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+# define MEMSET_SET_VEC0_AND_SET_RETURN(d, r) \
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+ vpbroadcastb d, %VEC0; \
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+ movq r, %rax
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-# define WMEMSET_VDUP_TO_VEC0_AND_SET_RETURN(d, r) \
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- movq r, %rax; \
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- vpbroadcastd d, %VEC0
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+# define WMEMSET_SET_VEC0_AND_SET_RETURN(d, r) \
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+ vpbroadcastd d, %VEC0; \
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+ movq r, %rax
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+
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+# define MEMSET_VDUP_TO_VEC0_HIGH()
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+# define MEMSET_VDUP_TO_VEC0_LOW()
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+
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+# define WMEMSET_VDUP_TO_VEC0_HIGH()
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+# define WMEMSET_VDUP_TO_VEC0_LOW()
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# define SECTION(p) p##.evex512
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# define MEMSET_SYMBOL(p,s) p##_avx512_##s
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diff --git a/sysdeps/x86_64/multiarch/memset-evex-unaligned-erms.S b/sysdeps/x86_64/multiarch/memset-evex-unaligned-erms.S
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index 64b09e77..63700215 100644
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--- a/sysdeps/x86_64/multiarch/memset-evex-unaligned-erms.S
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+++ b/sysdeps/x86_64/multiarch/memset-evex-unaligned-erms.S
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@@ -15,13 +15,19 @@
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# define VZEROUPPER
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-# define MEMSET_VDUP_TO_VEC0_AND_SET_RETURN(d, r) \
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- movq r, %rax; \
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- vpbroadcastb d, %VEC0
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+# define MEMSET_SET_VEC0_AND_SET_RETURN(d, r) \
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+ vpbroadcastb d, %VEC0; \
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+ movq r, %rax
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-# define WMEMSET_VDUP_TO_VEC0_AND_SET_RETURN(d, r) \
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- movq r, %rax; \
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- vpbroadcastd d, %VEC0
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+# define WMEMSET_SET_VEC0_AND_SET_RETURN(d, r) \
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+ vpbroadcastd d, %VEC0; \
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+ movq r, %rax
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+
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+# define MEMSET_VDUP_TO_VEC0_HIGH()
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+# define MEMSET_VDUP_TO_VEC0_LOW()
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+
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+# define WMEMSET_VDUP_TO_VEC0_HIGH()
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+# define WMEMSET_VDUP_TO_VEC0_LOW()
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# define SECTION(p) p##.evex
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# define MEMSET_SYMBOL(p,s) p##_evex_##s
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diff --git a/sysdeps/x86_64/multiarch/memset-vec-unaligned-erms.S b/sysdeps/x86_64/multiarch/memset-vec-unaligned-erms.S
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index f08b7323..a67f9833 100644
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--- a/sysdeps/x86_64/multiarch/memset-vec-unaligned-erms.S
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+++ b/sysdeps/x86_64/multiarch/memset-vec-unaligned-erms.S
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@@ -58,8 +58,10 @@
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#ifndef MOVQ
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# if VEC_SIZE > 16
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# define MOVQ vmovq
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+# define MOVD vmovd
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# else
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# define MOVQ movq
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+# define MOVD movd
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# endif
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#endif
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@@ -72,9 +74,17 @@
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#if defined USE_WITH_EVEX || defined USE_WITH_AVX512
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# define END_REG rcx
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# define LOOP_REG rdi
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+# define LESS_VEC_REG rax
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#else
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# define END_REG rdi
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# define LOOP_REG rdx
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+# define LESS_VEC_REG rdi
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+#endif
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+
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+#ifdef USE_XMM_LESS_VEC
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+# define XMM_SMALL 1
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+#else
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+# define XMM_SMALL 0
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#endif
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#define PAGE_SIZE 4096
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@@ -110,8 +120,12 @@ END_CHK (WMEMSET_CHK_SYMBOL (__wmemset_chk, unaligned))
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ENTRY (WMEMSET_SYMBOL (__wmemset, unaligned))
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shl $2, %RDX_LP
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- WMEMSET_VDUP_TO_VEC0_AND_SET_RETURN (%esi, %rdi)
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- jmp L(entry_from_bzero)
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+ WMEMSET_SET_VEC0_AND_SET_RETURN (%esi, %rdi)
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+ WMEMSET_VDUP_TO_VEC0_LOW()
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+ cmpq $VEC_SIZE, %rdx
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+ jb L(less_vec_no_vdup)
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+ WMEMSET_VDUP_TO_VEC0_HIGH()
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+ jmp L(entry_from_wmemset)
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END (WMEMSET_SYMBOL (__wmemset, unaligned))
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#endif
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@@ -123,7 +137,7 @@ END_CHK (MEMSET_CHK_SYMBOL (__memset_chk, unaligned))
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#endif
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ENTRY (MEMSET_SYMBOL (__memset, unaligned))
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- MEMSET_VDUP_TO_VEC0_AND_SET_RETURN (%esi, %rdi)
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+ MEMSET_SET_VEC0_AND_SET_RETURN (%esi, %rdi)
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# ifdef __ILP32__
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/* Clear the upper 32 bits. */
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mov %edx, %edx
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@@ -131,6 +145,8 @@ ENTRY (MEMSET_SYMBOL (__memset, unaligned))
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L(entry_from_bzero):
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cmpq $VEC_SIZE, %rdx
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jb L(less_vec)
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+ MEMSET_VDUP_TO_VEC0_HIGH()
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+L(entry_from_wmemset):
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cmpq $(VEC_SIZE * 2), %rdx
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ja L(more_2x_vec)
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/* From VEC and to 2 * VEC. No branch when size == VEC_SIZE. */
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@@ -179,27 +195,27 @@ END_CHK (MEMSET_CHK_SYMBOL (__memset_chk, unaligned_erms))
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# endif
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ENTRY_P2ALIGN (MEMSET_SYMBOL (__memset, unaligned_erms), 6)
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- MEMSET_VDUP_TO_VEC0_AND_SET_RETURN (%esi, %rdi)
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+ MEMSET_SET_VEC0_AND_SET_RETURN (%esi, %rdi)
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# ifdef __ILP32__
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/* Clear the upper 32 bits. */
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mov %edx, %edx
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# endif
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cmp $VEC_SIZE, %RDX_LP
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jb L(less_vec)
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+ MEMSET_VDUP_TO_VEC0_HIGH ()
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cmp $(VEC_SIZE * 2), %RDX_LP
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ja L(stosb_more_2x_vec)
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- /* From VEC and to 2 * VEC. No branch when size == VEC_SIZE.
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- */
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- VMOVU %VEC(0), (%rax)
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- VMOVU %VEC(0), -VEC_SIZE(%rax, %rdx)
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+ /* From VEC and to 2 * VEC. No branch when size == VEC_SIZE. */
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+ VMOVU %VEC(0), (%rdi)
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+ VMOVU %VEC(0), (VEC_SIZE * -1)(%rdi, %rdx)
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VZEROUPPER_RETURN
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#endif
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- .p2align 4,, 10
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+ .p2align 4,, 4
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L(last_2x_vec):
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#ifdef USE_LESS_VEC_MASK_STORE
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- VMOVU %VEC(0), (VEC_SIZE * 2 + LOOP_4X_OFFSET)(%rcx)
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- VMOVU %VEC(0), (VEC_SIZE * 3 + LOOP_4X_OFFSET)(%rcx)
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+ VMOVU %VEC(0), (VEC_SIZE * -2)(%rdi, %rdx)
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+ VMOVU %VEC(0), (VEC_SIZE * -1)(%rdi, %rdx)
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#else
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VMOVU %VEC(0), (VEC_SIZE * -2)(%rdi)
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VMOVU %VEC(0), (VEC_SIZE * -1)(%rdi)
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@@ -212,6 +228,7 @@ L(last_2x_vec):
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#ifdef USE_LESS_VEC_MASK_STORE
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.p2align 4,, 10
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L(less_vec):
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+L(less_vec_no_vdup):
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/* Less than 1 VEC. */
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# if VEC_SIZE != 16 && VEC_SIZE != 32 && VEC_SIZE != 64
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# error Unsupported VEC_SIZE!
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@@ -262,28 +279,18 @@ L(stosb_more_2x_vec):
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/* Fallthrough goes to L(loop_4x_vec). Tests for memset (2x, 4x]
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and (4x, 8x] jump to target. */
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L(more_2x_vec):
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-
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- /* Two different methods of setting up pointers / compare. The
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- two methods are based on the fact that EVEX/AVX512 mov
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- instructions take more bytes then AVX2/SSE2 mov instructions. As
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- well that EVEX/AVX512 machines also have fast LEA_BID. Both
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- setup and END_REG to avoid complex address mode. For EVEX/AVX512
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- this saves code size and keeps a few targets in one fetch block.
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- For AVX2/SSE2 this helps prevent AGU bottlenecks. */
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-#if defined USE_WITH_EVEX || defined USE_WITH_AVX512
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- /* If EVEX/AVX512 compute END_REG - (VEC_SIZE * 4 +
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- LOOP_4X_OFFSET) with LEA_BID. */
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-
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- /* END_REG is rcx for EVEX/AVX512. */
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- leaq -(VEC_SIZE * 4 + LOOP_4X_OFFSET)(%rdi, %rdx), %END_REG
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-#endif
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-
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- /* Stores to first 2x VEC before cmp as any path forward will
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- require it. */
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- VMOVU %VEC(0), (%rax)
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- VMOVU %VEC(0), VEC_SIZE(%rax)
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+ /* Store next 2x vec regardless. */
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+ VMOVU %VEC(0), (%rdi)
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+ VMOVU %VEC(0), (VEC_SIZE * 1)(%rdi)
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+ /* Two different methods of setting up pointers / compare. The two
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+ methods are based on the fact that EVEX/AVX512 mov instructions take
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+ more bytes then AVX2/SSE2 mov instructions. As well that EVEX/AVX512
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+ machines also have fast LEA_BID. Both setup and END_REG to avoid complex
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+ address mode. For EVEX/AVX512 this saves code size and keeps a few
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+ targets in one fetch block. For AVX2/SSE2 this helps prevent AGU
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+ bottlenecks. */
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#if !(defined USE_WITH_EVEX || defined USE_WITH_AVX512)
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/* If AVX2/SSE2 compute END_REG (rdi) with ALU. */
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addq %rdx, %END_REG
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@@ -292,6 +299,15 @@ L(more_2x_vec):
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cmpq $(VEC_SIZE * 4), %rdx
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jbe L(last_2x_vec)
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+
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+#if defined USE_WITH_EVEX || defined USE_WITH_AVX512
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+ /* If EVEX/AVX512 compute END_REG - (VEC_SIZE * 4 + LOOP_4X_OFFSET) with
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+ LEA_BID. */
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+
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+ /* END_REG is rcx for EVEX/AVX512. */
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+ leaq -(VEC_SIZE * 4 + LOOP_4X_OFFSET)(%rdi, %rdx), %END_REG
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+#endif
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+
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/* Store next 2x vec regardless. */
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VMOVU %VEC(0), (VEC_SIZE * 2)(%rax)
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VMOVU %VEC(0), (VEC_SIZE * 3)(%rax)
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@@ -355,65 +371,93 @@ L(stosb_local):
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/* Define L(less_vec) only if not otherwise defined. */
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.p2align 4
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L(less_vec):
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+ /* Broadcast esi to partial register (i.e VEC_SIZE == 32 broadcast to
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+ xmm). This is only does anything for AVX2. */
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+ MEMSET_VDUP_TO_VEC0_LOW ()
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+L(less_vec_no_vdup):
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#endif
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L(cross_page):
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#if VEC_SIZE > 32
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cmpl $32, %edx
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- jae L(between_32_63)
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+ jge L(between_32_63)
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#endif
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#if VEC_SIZE > 16
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cmpl $16, %edx
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- jae L(between_16_31)
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+ jge L(between_16_31)
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+#endif
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+#ifndef USE_XMM_LESS_VEC
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+ MOVQ %XMM0, %rcx
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#endif
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- MOVQ %XMM0, %rdi
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cmpl $8, %edx
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- jae L(between_8_15)
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+ jge L(between_8_15)
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cmpl $4, %edx
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- jae L(between_4_7)
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+ jge L(between_4_7)
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cmpl $1, %edx
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- ja L(between_2_3)
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- jb L(return)
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- movb %sil, (%rax)
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- VZEROUPPER_RETURN
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+ jg L(between_2_3)
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+ jl L(between_0_0)
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+ movb %sil, (%LESS_VEC_REG)
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+L(between_0_0):
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+ ret
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- /* Align small targets only if not doing so would cross a fetch
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- line. */
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+ /* Align small targets only if not doing so would cross a fetch line.
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+ */
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#if VEC_SIZE > 32
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.p2align 4,, SMALL_MEMSET_ALIGN(MOV_SIZE, RET_SIZE)
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/* From 32 to 63. No branch when size == 32. */
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L(between_32_63):
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- VMOVU %YMM0, (%rax)
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- VMOVU %YMM0, -32(%rax, %rdx)
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+ VMOVU %YMM0, (%LESS_VEC_REG)
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+ VMOVU %YMM0, -32(%LESS_VEC_REG, %rdx)
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VZEROUPPER_RETURN
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#endif
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#if VEC_SIZE >= 32
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- .p2align 4,, SMALL_MEMSET_ALIGN(MOV_SIZE, RET_SIZE)
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+ .p2align 4,, SMALL_MEMSET_ALIGN(MOV_SIZE, 1)
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L(between_16_31):
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/* From 16 to 31. No branch when size == 16. */
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- VMOVU %XMM0, (%rax)
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- VMOVU %XMM0, -16(%rax, %rdx)
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- VZEROUPPER_RETURN
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+ VMOVU %XMM0, (%LESS_VEC_REG)
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+ VMOVU %XMM0, -16(%LESS_VEC_REG, %rdx)
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+ ret
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#endif
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- .p2align 4,, SMALL_MEMSET_ALIGN(3, RET_SIZE)
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+ /* Move size is 3 for SSE2, EVEX, and AVX512. Move size is 4 for AVX2.
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+ */
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+ .p2align 4,, SMALL_MEMSET_ALIGN(3 + XMM_SMALL, 1)
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L(between_8_15):
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/* From 8 to 15. No branch when size == 8. */
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- movq %rdi, (%rax)
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- movq %rdi, -8(%rax, %rdx)
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- VZEROUPPER_RETURN
|
|
+#ifdef USE_XMM_LESS_VEC
|
|
+ MOVQ %XMM0, (%rdi)
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+ MOVQ %XMM0, -8(%rdi, %rdx)
|
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+#else
|
|
+ movq %rcx, (%LESS_VEC_REG)
|
|
+ movq %rcx, -8(%LESS_VEC_REG, %rdx)
|
|
+#endif
|
|
+ ret
|
|
|
|
- .p2align 4,, SMALL_MEMSET_ALIGN(2, RET_SIZE)
|
|
+ /* Move size is 2 for SSE2, EVEX, and AVX512. Move size is 4 for AVX2.
|
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+ */
|
|
+ .p2align 4,, SMALL_MEMSET_ALIGN(2 << XMM_SMALL, 1)
|
|
L(between_4_7):
|
|
/* From 4 to 7. No branch when size == 4. */
|
|
- movl %edi, (%rax)
|
|
- movl %edi, -4(%rax, %rdx)
|
|
- VZEROUPPER_RETURN
|
|
+#ifdef USE_XMM_LESS_VEC
|
|
+ MOVD %XMM0, (%rdi)
|
|
+ MOVD %XMM0, -4(%rdi, %rdx)
|
|
+#else
|
|
+ movl %ecx, (%LESS_VEC_REG)
|
|
+ movl %ecx, -4(%LESS_VEC_REG, %rdx)
|
|
+#endif
|
|
+ ret
|
|
|
|
- .p2align 4,, SMALL_MEMSET_ALIGN(3, RET_SIZE)
|
|
+ /* 4 * XMM_SMALL for the third mov for AVX2. */
|
|
+ .p2align 4,, 4 * XMM_SMALL + SMALL_MEMSET_ALIGN(3, 1)
|
|
L(between_2_3):
|
|
/* From 2 to 3. No branch when size == 2. */
|
|
- movw %di, (%rax)
|
|
- movb %dil, -1(%rax, %rdx)
|
|
- VZEROUPPER_RETURN
|
|
+#ifdef USE_XMM_LESS_VEC
|
|
+ movb %sil, (%rdi)
|
|
+ movb %sil, 1(%rdi)
|
|
+ movb %sil, -1(%rdi, %rdx)
|
|
+#else
|
|
+ movw %cx, (%LESS_VEC_REG)
|
|
+ movb %sil, -1(%LESS_VEC_REG, %rdx)
|
|
+#endif
|
|
+ ret
|
|
END (MEMSET_SYMBOL (__memset, unaligned_erms))
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--
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GitLab
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