Fix regression caused by 2fa631e

* POWER8/9 feature checks were enabled even if the toolchain didn't support AT_HWCAP2
* Add detection if we need to include <linux/auxvec.h>

CMakeLists.txt

@@ -326,6 +326,14 @@ if(HAVE_SYS_SDT_H)
 endif()
 check_include_file(unistd.h    HAVE_UNISTD_H)
 
+#
+# Check for Linux includes
+#
+check_include_file(linux/auxvec.h HAVE_LINUX_AUXVEC_H)
+if(HAVE_LINUX_AUXVEC_H)
+    add_definitions(-DHAVE_LINUX_AUXVEC_H)
+endif()
+
 #
 # Check to see if we have large file support
 #
@@ -685,8 +693,13 @@ if(WITH_OPTIM)
         if(WITH_POWER9)
             check_power9_intrinsics()
         endif()
-        if(HAVE_VMX OR HAVE_POWER8_INTRIN OR HAVE_POWER9_INTRIN)
+        if(POWER8_NEED_AUXVEC_H OR POWER9_NEED_AUXVEC_H)
+            add_definitions(-DPOWER_NEED_AUXVEC_H)
+        endif()
+        if(HAVE_POWER8_INTRIN OR HAVE_POWER9_INTRIN)
             add_definitions(-DPOWER_FEATURES)
+        endif()
+        if(HAVE_VMX OR HAVE_POWER8_INTRIN OR HAVE_POWER9_INTRIN)
             list(APPEND ZLIB_ARCH_HDRS ${ARCHDIR}/power_features.h)
             list(APPEND ZLIB_ARCH_SRCS ${ARCHDIR}/power_features.c)
         endif()

arch/power/power_features.c

@@ -1,12 +1,15 @@
 /* power_features.c - POWER feature check
  * Copyright (C) 2020 Matheus Castanho <[email protected]>, IBM
- * Copyright (C) 2021-2022 Mika T. Lindqvist <[email protected]>
+ * Copyright (C) 2021-2024 Mika T. Lindqvist <[email protected]>
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
 #ifdef HAVE_SYS_AUXV_H
 #  include <sys/auxv.h>
 #endif
+#ifdef POWER_NEED_AUXVEC_H
+#  include <linux/auxvec.h>
+#endif
 #ifdef __FreeBSD__
 #  include <machine/cpu.h>
 #endif

cmake/detect-intrinsics.cmake

@@ -355,6 +355,21 @@ macro(check_power8_intrinsics)
         }"
         HAVE_POWER8_INTRIN
     )
+    if(NOT HAVE_POWER8_INTRIN AND HAVE_LINUX_AUXVEC_H)
+        check_c_source_compiles(
+            "#include <sys/auxv.h>
+            #include <linux/auxvec.h>
+            int main() {
+                return (getauxval(AT_HWCAP2) & PPC_FEATURE2_ARCH_2_07);
+            }"
+            HAVE_POWER8_INTRIN2
+        )
+        if(HAVE_POWER8_INTRIN2)
+            set(POWER8_NEED_AUXVEC_H 1)
+            set(HAVE_POWER8_INTRIN ${HAVE_POWER8_INTRIN2} CACHE INTERNAL "Have POWER8 intrinsics" FORCE)
+            unset(HAVE_POWER8_INTRIN2 CACHE)
+        endif()
+    endif()
     set(CMAKE_REQUIRED_FLAGS)
 endmacro()
 
@@ -413,6 +428,21 @@ macro(check_power9_intrinsics)
         }"
         HAVE_POWER9_INTRIN
     )
+    if(NOT HAVE_POWER9_INTRIN AND HAVE_LINUX_AUXVEC_H)
+        check_c_source_compiles(
+            "#include <sys/auxv.h>
+            #include <linux/auxvec.h>
+            int main() {
+                return (getauxval(AT_HWCAP2) & PPC_FEATURE2_ARCH_3_00);
+            }"
+            HAVE_POWER9_INTRIN2
+        )
+        if(HAVE_POWER9_INTRIN2)
+            set(POWER9_NEED_AUXVEC_H 1)
+            set(HAVE_POWER9_INTRIN ${HAVE_POWER9_INTRIN2} CACHE INTERNAL "Have POWER9 intrinsics" FORCE)
+            unset(HAVE_POWER9_INTRIN2 CACHE)
+        endif()
+    endif()
     set(CMAKE_REQUIRED_FLAGS)
 endmacro()