atomic: Detect 32bit and 64bit atomic builtins separately.

Some 32bit platforms provide 32bit but not 64bit atomics, detect and
distinctly set/use HAVE_ATOMIC_BUILTINS/HAVE_ATOMIC_BUILTINS64 and
USE_ATOMICS_BUILTINS/USE_ATOMICS_BUILTINS64.

These platforms NEED_ATOMICS_GENERIC64 as 64bit implementation.

* configure.in():
  Use stdint.h's uint{32,64}_t as atomic type for testing atomic builtins
  when available, otherwise "unsigned int" for 32bit testing and
  "unsigned long long" as 64bit.

* configure.in():
  AC_TRY_RUN each 32bit and 64bit type separately, the former determining
  HAVE_ATOMIC_BUILTINS and the latter HAVE_ATOMIC_BUILTINS64.

* include/arch/unix/apr_arch_atomic.h():
  Define USE_ATOMICS_BUILTINS64 when HAVE_ATOMIC_BUILTINS64, otherise
  define NEED_ATOMICS_GENERIC64

* include/arch/unix/apr_arch_atomic.h():
  Check defined(__powerpc__) for USE_ATOMICS_PPC.

* atomic/unix/builtins64.c():
  Implement for USE_ATOMICS_BUILTINS64 only.


BZ 63566.
Merge r1902266 from trunk.
Submitted by: ylavic


git-svn-id: https://svn.apache.org/repos/asf/apr/apr/branches/1.7.x@1902290 13f79535-47bb-0310-9956-ffa450edef68

3 files changed, 105 insertions, 9 deletions

diff --git a/atomic/unix/builtins64.c b/atomic/unix/builtins64.c
index 0f6edffbb..7d8422548 100644
--- a/atomic/unix/builtins64.c
+++ b/atomic/unix/builtins64.c
@@ -16,7 +16,7 @@
 
 #include "apr_arch_atomic.h"
 
-#ifdef USE_ATOMICS_BUILTINS
+#ifdef USE_ATOMICS_BUILTINS64
 
 #if defined(__arm__) || defined(__powerpc__) || defined(__powerpc64__)
 #define WEAK_MEMORY_ORDERING 1
@@ -106,4 +106,4 @@ APR_DECLARE(apr_uint64_t) apr_atomic_xchg64(volatile apr_uint64_t *mem, apr_uint
 #endif
 }
 
-#endif /* USE_ATOMICS_BUILTINS */
+#endif /* USE_ATOMICS_BUILTINS64 */
diff --git a/configure.in b/configure.in
index 2fbd0a131..1cdc4653a 100644
--- a/configure.in
+++ b/configure.in
@@ -465,11 +465,18 @@ case "$host:$CC" in
         ;;
 esac
 
-AC_CACHE_CHECK([whether the compiler provides atomic builtins], [ap_cv_atomic_builtins],
+AC_CACHE_CHECK([whether the compiler provides 32bit atomic builtins], [ap_cv_atomic_builtins],
 [AC_TRY_RUN([
+#if HAVE_STDINT_H
+#include <stdint.h>
+#endif
 int main(int argc, const char *const *argv)
 {
-    unsigned long val = 1010, tmp, *mem = &val;
+#if HAVE_STDINT_H
+    uint32_t val = 1010, tmp, *mem = &val;
+#else
+    unsigned int val = 1010, tmp, *mem = &val;
+#endif
 
     if (__sync_fetch_and_add(&val, 1010) != 1010 || val != 2020)
         return 1;
@@ -495,11 +502,18 @@ int main(int argc, const char *const *argv)
     return 0;
 }], [ap_cv_atomic_builtins=yes], [ap_cv_atomic_builtins=no], [ap_cv_atomic_builtins=no])])
 
-AC_CACHE_CHECK([whether the compiler provides __atomic builtins], [ap_cv__atomic_builtins],
+AC_CACHE_CHECK([whether the compiler provides 32bit __atomic builtins], [ap_cv__atomic_builtins],
 [AC_TRY_RUN([
+#if HAVE_STDINT_H
+#include <stdint.h>
+#endif
 int main(int argc, const char *const *argv)
 {
-    unsigned long val = 1010, tmp, *mem = &val, *ptmp;
+#if HAVE_STDINT_H
+    uint32_t val = 1010, tmp, *mem = &val, *ptmp;
+#else
+    unsigned int val = 1010, tmp, *mem = &val, *ptmp;
+#endif
 
     if (__atomic_fetch_add(&val, 1010, __ATOMIC_SEQ_CST) != 1010 || val != 2020)
         return 1;
@@ -528,9 +542,84 @@ int main(int argc, const char *const *argv)
 }], [ap_cv__atomic_builtins=yes], [ap_cv__atomic_builtins=no], [ap_cv__atomic_builtins=no])])
 
 if test "$ap_cv_atomic_builtins" = "yes" -o "$ap_cv__atomic_builtins" = "yes"; then
-    AC_DEFINE(HAVE_ATOMIC_BUILTINS, 1, [Define if compiler provides atomic builtins])
+    AC_DEFINE(HAVE_ATOMIC_BUILTINS, 1, [Define if compiler provides 32bit atomic builtins])
     if test "$ap_cv__atomic_builtins" = "yes"; then
-        AC_DEFINE(HAVE__ATOMIC_BUILTINS, 1, [Define if compiler provides __atomic builtins])
+        AC_DEFINE(HAVE__ATOMIC_BUILTINS, 1, [Define if compiler provides 32bit __atomic builtins])
+    fi
+fi
+
+AC_CACHE_CHECK([whether the compiler provides 64bit atomic builtins], [ap_cv_atomic_builtins64],
+[AC_TRY_RUN([
+#if HAVE_STDINT_H
+#include <stdint.h>
+#endif
+int main(int argc, const char *const *argv)
+{
+#if HAVE_STDINT_H
+    uint64_t val = 1010, tmp, *mem = &val;
+#else
+    unsigned long long val = 1010, tmp, *mem = &val;
+#endif
+
+    if (__sync_fetch_and_add(&val, 1010) != 1010 || val != 2020)
+        return 1;
+
+    tmp = val;
+    if (__sync_fetch_and_sub(mem, 1010) != tmp || val != 1010)
+        return 1;
+
+    if (__sync_sub_and_fetch(&val, 1010) != 0 || val != 0)
+        return 1;
+
+    tmp = 3030;
+    if (__sync_val_compare_and_swap(mem, 0, tmp) != 0 || val != tmp)
+        return 1;
+
+    __sync_synchronize();
+    if (__sync_lock_test_and_set(&val, 4040) != 3030)
+        return 1;
+
+    return 0;
+}], [ap_cv_atomic_builtins64=yes], [ap_cv_atomic_builtins64=no], [ap_cv_atomic_builtins64=no])])
+
+AC_CACHE_CHECK([whether the compiler provides 64bit __atomic builtins], [ap_cv__atomic_builtins64],
+[AC_TRY_RUN([
+#if HAVE_STDINT_H
+#include <stdint.h>
+#endif
+int main(int argc, const char *const *argv)
+{
+#if HAVE_STDINT_H
+    uint64_t val = 1010, tmp, *mem = &val;
+#else
+    unsigned long long val = 1010, tmp, *mem = &val;
+#endif
+
+    if (__atomic_fetch_add(&val, 1010, __ATOMIC_SEQ_CST) != 1010 || val != 2020)
+        return 1;
+
+    tmp = val;
+    if (__atomic_fetch_sub(mem, 1010, __ATOMIC_SEQ_CST) != tmp || val != 1010)
+        return 1;
+
+    if (__atomic_sub_fetch(&val, 1010, __ATOMIC_SEQ_CST) != 0 || val != 0)
+        return 1;
+
+    tmp = val;
+    if (!__atomic_compare_exchange_n(mem, &tmp, 3030, 0, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST)
+            || tmp != 0)
+        return 1;
+
+    if (__atomic_exchange_n(&val, 4040, __ATOMIC_SEQ_CST) != 3030)
+        return 1;
+
+    return 0;
+}], [ap_cv__atomic_builtins64=yes], [ap_cv__atomic_builtins64=no], [ap_cv__atomic_builtins64=no])])
+
+if test "$ap_cv_atomic_builtins64" = "yes" -o "$ap_cv__atomic_builtins64" = "yes"; then
+    AC_DEFINE(HAVE_ATOMIC_BUILTINS64, 1, [Define if compiler provides 64bit atomic builtins])
+    if test "$ap_cv__atomic_builtins64" = "yes"; then
+        AC_DEFINE(HAVE__ATOMIC_BUILTINS64, 1, [Define if compiler provides 64bit __atomic builtins])
     fi
 fi
 
diff --git a/include/arch/unix/apr_arch_atomic.h b/include/arch/unix/apr_arch_atomic.h
index 559257deb..ce771ad9c 100644
--- a/include/arch/unix/apr_arch_atomic.h
+++ b/include/arch/unix/apr_arch_atomic.h
@@ -26,6 +26,11 @@
 /* noop */
 #elif HAVE_ATOMIC_BUILTINS
 #   define USE_ATOMICS_BUILTINS
+#   if HAVE_ATOMIC_BUILTINS64
+#   define USE_ATOMICS_BUILTINS64
+#   else
+#   define NEED_ATOMICS_GENERIC64
+#   endif
 #elif defined(SOLARIS2) && SOLARIS2 >= 10
 #   define USE_ATOMICS_SOLARIS
 #   define NEED_ATOMICS_GENERIC64
@@ -36,7 +41,9 @@
 #elif defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
 #   define USE_ATOMICS_IA32
 #   define NEED_ATOMICS_GENERIC64
-#elif defined(__GNUC__) && (defined(__PPC__) || defined(__ppc__))
+#elif defined(__GNUC__) && (defined(__powerpc__) \
+                            || defined(__PPC__) \
+                            || defined(__ppc__))
 #   define USE_ATOMICS_PPC
 #   define NEED_ATOMICS_GENERIC64
 #elif defined(__GNUC__) && (defined(__s390__) || defined(__s390x__))