From: Nathan Moinvaziri <nathan@nathanm.com>
Date: Thu, 21 May 2020 17:56:54 +0000 (-0700)
Subject: Remove additional byte comparison check in compare258 SSE4 and AVX2 functions.
X-Git-Tag: 1.9.9-b1~295
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=de7cfabb48c88bdba6120448f080b8f6dd941f65;p=thirdparty%2Fzlib-ng.git

Remove additional byte comparison check in compare258 SSE4 and AVX2 functions.
---

diff --git a/arch/x86/compare258_avx.c b/arch/x86/compare258_avx.c
index 0399abca8..74ca87ac9 100644
--- a/arch/x86/compare258_avx.c
+++ b/arch/x86/compare258_avx.c
@@ -51,13 +51,7 @@ static inline int32_t compare258_unaligned_avx2_static(const unsigned char *src0
     if (*(uint16_t *)src0 != *(uint16_t *)src1)
         return (*src0 == *src1);
 
-    src0 += 2, src1 += 2;
-    if (*src0 != *src1)
-        return 2;
-    if (src0[1] != src1[1])
-        return 3;
-
-    return compare256_unaligned_avx2_static(src0, src1) + 2;
+    return compare256_unaligned_avx2_static(src0+2, src1+2) + 2;
 }
 
 int32_t compare258_unaligned_avx2(const unsigned char *src0, const unsigned char *src1) {
diff --git a/arch/x86/compare258_sse.c b/arch/x86/compare258_sse.c
index 3e5e4eef3..27bae0510 100644
--- a/arch/x86/compare258_sse.c
+++ b/arch/x86/compare258_sse.c
@@ -58,14 +58,7 @@ static inline int32_t compare258_unaligned_sse4_static(const unsigned char *src0
     if (*(uint16_t *)src0 != *(uint16_t *)src1)
         return (*src0 == *src1);
 
-    src0 += 2, src1 += 2;
-
-    if (*src0 != *src1)
-        return 2;
-    if (src0[1] != src1[1])
-        return 3;
-
-    return compare256_unaligned_sse4_static(src0, src1) + 2;
+    return compare256_unaligned_sse4_static(src0+2, src1+2) + 2;
 }
 
 int32_t compare258_unaligned_sse4(const unsigned char *src0, const unsigned char *src1) {
diff --git a/compare258.c b/compare258.c
index db212d138..7763bb6a1 100644
--- a/compare258.c
+++ b/compare258.c
@@ -38,8 +38,6 @@ static inline int32_t compare258_c_static(const unsigned char *src0, const unsig
     if (*src0 != *src1)
         return 1;
     src0 += 1, src1 += 1;
-    if (*src0 != *src1)
-        return 2;
 
     return compare256_c_static(src0, src1) + 2;
 }
@@ -120,13 +118,7 @@ static inline int32_t compare258_unaligned_32_static(const unsigned char *src0,
     if (*(uint16_t *)src0 != *(uint16_t *)src1)
         return (*src0 == *src1);
 
-    src0 += 2, src1 += 2;
-    if (*src0 != *src1)
-        return 2;
-    if (src0[1] != src1[1])
-        return 3;
-
-    return compare256_unaligned_32_static(src0, src1) + 2;
+    return compare256_unaligned_32_static(src0+2, src1+2) + 2;
 }
 
 int32_t compare258_unaligned_32(const unsigned char *src0, const unsigned char *src1) {
@@ -166,13 +158,7 @@ static inline int32_t compare258_unaligned_64_static(const unsigned char *src0,
     if (*(uint16_t *)src0 != *(uint16_t *)src1)
         return (*src0 == *src1);
 
-    src0 += 2, src1 += 2;
-    if (*src0 != *src1)
-        return 2;
-    if (src0[1] != src1[1])
-        return 3;
-
-    return compare256_unaligned_64_static(src0, src1) + 2;
+    return compare256_unaligned_64_static(src0+2, src1+2) + 2;
 }
 
 int32_t compare258_unaligned_64(const unsigned char *src0, const unsigned char *src1) {