From: Hans Kristian Rosbach <hk-git@circlestorm.org>
Date: Sat, 4 Feb 2023 21:19:40 +0000 (+0100)
Subject: Remove FORCE_TZCNT/X86_NOCHECK_TZCNT
X-Git-Tag: 2.1.0-beta1~68
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=17d98072a97d5b29c7b8f24133f2abf263fa93b4;p=thirdparty%2Fzlib-ng.git

Remove FORCE_TZCNT/X86_NOCHECK_TZCNT
---

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 48e09d521..27ce9f477 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -112,7 +112,6 @@ elseif(BASEARCH_S360_FOUND)
     option(WITH_DFLTCC_INFLATE "Build with DFLTCC intrinsics for decompression on IBM Z" OFF)
     option(WITH_CRC32_VX "Build with vectorized CRC32 on IBM Z" ON)
 elseif(BASEARCH_X86_FOUND)
-    option(FORCE_TZCNT "Always assume CPU is TZCNT capable" OFF)
     option(WITH_AVX2 "Build with AVX2" ON)
     option(WITH_AVX512 "Build with AVX512" ON)
     option(WITH_AVX512VNNI "Build with AVX512 VNNI extensions" ON)
@@ -819,10 +818,6 @@ if(WITH_OPTIM)
                 set(WITH_SSE4 OFF)
             endif()
         endif()
-        if(FORCE_TZCNT)
-            add_definitions(-DX86_NOCHECK_TZCNT)
-        endif()
-        add_feature_info(FORCE_TZCNT FORCE_TZCNT "Assume CPU is TZCNT capable")
         if(WITH_SSE2)
             check_sse2_intrinsics()
             if(HAVE_SSE2_INTRIN)
diff --git a/README.md b/README.md
index a40980a07..5b8e8ccdc 100644
--- a/README.md
+++ b/README.md
@@ -209,7 +209,6 @@ Advanced Build Options
 | CMake                           | configure             | Description                                                         | Default                |
 |:--------------------------------|:----------------------|:--------------------------------------------------------------------|------------------------|
 | FORCE_SSE2                      | --force-sse2          | Skip runtime check for SSE2 instructions (Always on for x86_64)     | OFF (x86)              |
-| FORCE_TZCNT                     | --force-tzcnt         | Skip runtime check for TZCNT instructions                           | OFF                    |
 | WITH_AVX2                       |                       | Build with AVX2 intrinsics                                          | ON                     |
 | WITH_AVX512                     |                       | Build with AVX512 intrinsics                                        | ON                     |
 | WITH_AVX512VNNI                 |                       | Build with AVX512VNNI intrinsics                                    | ON                     |
diff --git a/arch/x86/x86_features.c b/arch/x86/x86_features.c
index 4c7563eab..d1ac51c55 100644
--- a/arch/x86/x86_features.c
+++ b/arch/x86/x86_features.c
@@ -122,7 +122,4 @@ void Z_INTERNAL x86_check_features(void) {
         x86_cpu_has_avx512vnni = 0;
         x86_cpu_has_vpclmulqdq = 0;
     }
-#ifdef X86_NOCHECK_TZCNT
-    Assert(!!x86_cpu_has_tzcnt, "TZCNT is not available");
-#endif
 }
diff --git a/configure b/configure
index 9cd570239..c0f9524b5 100755
--- a/configure
+++ b/configure
@@ -103,7 +103,6 @@ buildcrc32vx=1
 floatabi=
 native=0
 forcesse2=0
-forcetzcnt=0
 # For CPUs that can benefit from AVX512, it seems GCC generates suboptimal
 # instruction scheduling unless you specify a reasonable -mtune= target
 avx512flag="-mavx512f -mavx512dq -mavx512bw -mavx512vl -mtune=cascadelake"
@@ -177,7 +176,6 @@ case "$1" in
       echo '    [--without-crc32-vx]        Build without vectorized CRC32 on IBM Z' | tee -a configure.log
       echo '    [--with-reduced-mem]        Reduced memory usage for special cases (reduces performance)' | tee -a configure.log
       echo '    [--force-sse2]              Assume SSE2 instructions are always available (disabled by default on x86, enabled on x86_64)' | tee -a configure.log
-      echo '    [--force-tzcnt]             Assume TZCNT instructions are always available (disabled by default)' | tee -a configure.log
       echo '    [--native]                  Compiles with full instruction set supported on this host' | tee -a configure.log
         exit 0 ;;
     -p*=* | --prefix=*) prefix=$(echo $1 | sed 's/.*=//'); shift ;;
@@ -211,7 +209,6 @@ case "$1" in
     --without-crc32-vx) buildcrc32vx=0; shift ;;
     --with-reduced-mem) reducedmem=1; shift ;;
     --force-sse2) forcesse2=1; shift ;;
-    --force-tzcnt) forcetzcnt=1; shift ;;
     -n | --native) native=1; shift ;;
     -a*=* | --archs=*) ARCHS=$(echo $1 | sed 's/.*=//'); shift ;;
     --sysconfdir=*) echo "ignored option: --sysconfdir" | tee -a configure.log; shift ;;
@@ -1652,11 +1649,6 @@ case "${ARCH}" in
             if test ${HAVE_XSAVE_INTRIN} -eq 0; then
                 xsaveflag=""
             fi
-
-            if test $forcetzcnt -eq 1; then
-                CFLAGS="${CFLAGS} -DX86_NOCHECK_TZCNT"
-                SFLAGS="${SFLAGS} -DX86_NOCHECK_TZCNT"
-            fi
         fi
     ;;