From 28dfdaa8a3c5add48dcaf56086a9306a357e6e6b Mon Sep 17 00:00:00 2001
From: Maksim Kita <kitaetoya@gmail.com>
Date: Fri, 16 Apr 2021 00:17:26 +0300
Subject: [PATCH] Updated x86 arm power_pc check feature using constructor

---
 arch/power/power.c |  2 +-
 arch/power/power.h |  2 --
 crc32.c            |  1 -
 functable.c        | 20 --------------------
 4 files changed, 1 insertion(+), 24 deletions(-)

diff --git a/arch/power/power.c b/arch/power/power.c
index f93b586d5..b277c2637 100644
--- a/arch/power/power.c
+++ b/arch/power/power.c
@@ -8,7 +8,7 @@
 
 Z_INTERNAL int power_cpu_has_arch_2_07;
 
-void Z_INTERNAL power_check_features(void) {
+static void __attribute__((constructor)) power_check_features(void) {
     unsigned long hwcap2;
     hwcap2 = getauxval(AT_HWCAP2);
 
diff --git a/arch/power/power.h b/arch/power/power.h
index b36c26141..0bf0b1ec4 100644
--- a/arch/power/power.h
+++ b/arch/power/power.h
@@ -8,6 +8,4 @@
 
 extern int power_cpu_has_arch_2_07;
 
-void Z_INTERNAL power_check_features(void);
-
 #endif /* POWER_H_ */
diff --git a/crc32.c b/crc32.c
index 4b488e617..e18c0c223 100644
--- a/crc32.c
+++ b/crc32.c
@@ -181,7 +181,6 @@ Z_INTERNAL void crc_finalize(deflate_state *const s) {
 
 Z_INTERNAL void crc_reset(deflate_state *const s) {
 #ifdef X86_PCLMULQDQ_CRC
-    x86_check_features();
     if (x86_cpu_has_pclmulqdq) {
         crc_fold_init(s);
         return;
diff --git a/functable.c b/functable.c
index f20123358..c3c3707ee 100644
--- a/functable.c
+++ b/functable.c
@@ -136,27 +136,11 @@ extern uint32_t longest_match_unaligned_avx2(deflate_state *const s, Pos cur_mat
 
 Z_INTERNAL Z_TLS struct functable_s functable;
 
-Z_INTERNAL void cpu_check_features(void)
-{
-    static int features_checked = 0;
-    if (features_checked)
-        return;
-#if defined(X86_FEATURES)
-    x86_check_features();
-#elif defined(ARM_FEATURES)
-    arm_check_features();
-#elif defined(POWER_FEATURES)
-    power_check_features();
-#endif
-    features_checked = 1;
-}
-
 /* stub functions */
 Z_INTERNAL void insert_string_stub(deflate_state *const s, const uint32_t str, uint32_t count) {
     // Initialize default
 
     functable.insert_string = &insert_string_c;
-    cpu_check_features();
 
 #ifdef X86_SSE42_CRC_HASH
     if (x86_cpu_has_sse42)
@@ -186,7 +170,6 @@ Z_INTERNAL Pos quick_insert_string_stub(deflate_state *const s, const uint32_t s
 Z_INTERNAL void slide_hash_stub(deflate_state *s) {
 
     functable.slide_hash = &slide_hash_c;
-    cpu_check_features();
 
 #ifdef X86_SSE2
 #  if !defined(__x86_64__) && !defined(_M_X64) && !defined(X86_NOCHECK_SSE2)
@@ -214,7 +197,6 @@ Z_INTERNAL void slide_hash_stub(deflate_state *s) {
 Z_INTERNAL uint32_t adler32_stub(uint32_t adler, const unsigned char *buf, size_t len) {
     // Initialize default
     functable.adler32 = &adler32_c;
-    cpu_check_features();
 
 #ifdef ARM_NEON_ADLER32
 #  ifndef ARM_NOCHECK_NEON
@@ -378,8 +360,6 @@ Z_INTERNAL uint32_t crc32_stub(uint32_t crc, const unsigned char *buf, uint64_t
            "crc32_z takes size_t but internally we have a uint64_t len");
     /* return a function pointer for optimized arches here after a capability test */
 
-    cpu_check_features();
-
     if (use_byfour) {
 #if BYTE_ORDER == LITTLE_ENDIAN
         functable.crc32 = crc32_little;