Darwin: Handle linker '-no_deduplicate' option.

Newer linker support an option to disable deduplication of entities.
This speeds up linking and can improve debug experience.  Adopting the
same criteria as clang in adding the option.

Signed-off-by: Iain Sandoe <iain@sandoe.co.uk>

gcc/ChangeLog:

	* config.in: Regenerate.
	* config/darwin.h (DARWIN_LD_NO_DEDUPLICATE): New.
	(LINK_SPEC): Handle -no_deduplicate.
	* configure: Regenerate.
	* configure.ac: Detect linker support for -no_deduplicate.

4 files changed, 60 insertions, 7 deletions

diff --git a/gcc/config.in b/gcc/config.in
index 353d1bc..183d0dfc 100644
--- a/gcc/config.in
+++ b/gcc/config.in
@@ -2375,6 +2375,12 @@
 #endif
 
 
+/* Define to 1 if ld64 supports '-no_deduplicate'. */
+#ifndef USED_FOR_TARGET
+#undef LD64_HAS_NO_DEDUPLICATE
+#endif
+
+
 /* Define to 1 if ld64 supports '-platform_version'. */
 #ifndef USED_FOR_TARGET
 #undef LD64_HAS_PLATFORM_VERSION
diff --git a/gcc/config/darwin.h b/gcc/config/darwin.h
index ccfe01e..c3e28e2 100644
--- a/gcc/config/darwin.h
+++ b/gcc/config/darwin.h
@@ -287,6 +287,19 @@ extern GTY(()) int darwin_ms_struct;
 #define DARWIN_RDYNAMIC "%{rdynamic:%nrdynamic is not supported}"
 #endif
 
+#if LD64_HAS_NO_DEDUPLICATE
+/* What we want is "when the optimization level is debug OR when it is
+   a compile & link job with implied O0 optimization".  */
+#define DARWIN_LD_NO_DEDUPLICATE \
+  "%{O0|O1|O|Og: -no_deduplicate} \
+   %{!O*:\
+     %{.c|.cc|.C|.cpp|.cp|.c++|.cxx|.CPP|.m|.mm|.s|.S|.i|.ii|.mi|.mii|\
+       .f|.for|.ftn|.fpp|.f90|.f95|.f03|.f08|.f77|.F|.F90|.F95|.F03|.F08|\
+       .d|.mod: -no_deduplicate }} "
+#else
+#define DARWIN_LD_NO_DEDUPLICATE ""
+#endif
+
 #if LD64_HAS_MACOS_VERSION_MIN
 # define DARWIN_PLATFORM_ID \
   "%{mmacosx-version-min=*:-macos_version_min %*} "
@@ -403,10 +416,14 @@ extern GTY(()) int darwin_ms_struct;
     %(linker)" \
     DARWIN_LD_DEMANGLE \
     LINK_PLUGIN_SPEC \
+    DARWIN_LD_NO_DEDUPLICATE \
     "%{flto*:%<fcompare-debug*} \
      %{flto} %{fno-lto} %{flto=*} \
-    %l " \
+     %{static}%{!static:%{!dynamic:-dynamic}} \
+     %{force_cpusubtype_ALL:-arch %(darwin_arch)} \
+     %{!force_cpusubtype_ALL:-arch %(darwin_subarch)} "\
     DARWIN_PLATFORM_ID \
+    " %l " \
     LINK_COMPRESS_DEBUG_SPEC \
    "%X %{s} %{t} %{Z} %{u*} \
     %{e*} %{r} \
@@ -493,9 +510,8 @@ extern GTY(()) int darwin_ms_struct;
    Note that options taking arguments may appear multiple times on a command
    line with different arguments each time, so put a * after their names so
    all of them get passed.  */
-#define LINK_SPEC  \
-  "%{static}%{!static:%{!dynamic:-dynamic}} \
-   %:remove-outfile(-ldl) \
+#define LINK_SPEC \
+   "%:remove-outfile(-ldl) \
    %:remove-outfile(-lm) \
    %:remove-outfile(-lpthread) \
    %{fgnu-runtime: %{static|static-libgcc: \
@@ -511,9 +527,7 @@ extern GTY(()) int darwin_ms_struct;
    %{static|static-libgm2:%:replace-outfile(-lm2iso libm2iso.a%s)}\
    %{static|static-libgm2:%:replace-outfile(-lm2min libm2min.a%s)}\
    %{static|static-libgm2:%:replace-outfile(-lm2log libm2log.a%s)}\
-   %{static|static-libgm2:%:replace-outfile(-lm2cor libm2cor.a%s)}\
-  %{force_cpusubtype_ALL:-arch %(darwin_arch)} \
-   %{!force_cpusubtype_ALL:-arch %(darwin_subarch)} "\
+   %{static|static-libgm2:%:replace-outfile(-lm2cor libm2cor.a%s)} "\
    LINK_SYSROOT_SPEC \
    "%{!multiply_defined*:%{shared-libgcc: \
      %:version-compare(< 10.5 mmacosx-version-min= -multiply_defined) \
diff --git a/gcc/configure b/gcc/configure
index eb57959..4a751d9 100755
--- a/gcc/configure
+++ b/gcc/configure
@@ -32722,6 +32722,7 @@ if test x"$ld64_flag" = x"yes"; then
   gcc_cv_ld64_platform_version=0
   gcc_cv_ld64_macos_version_min=0
   gcc_cv_ld64_demangle=0
+  gcc_cv_ld64_no_deduplicate=0
 
   if test "$build" = "$host"; then
     darwin_try_test=1
@@ -32751,6 +32752,9 @@ $as_echo "$gcc_cv_ld64_major" >&6; }
     if test "$gcc_cv_ld64_major" -ge 236; then
       gcc_cv_ld64_export_dynamic=1
     fi
+    if test "$gcc_cv_ld64_major" -ge 262; then
+      gcc_cv_ld64_no_deduplicate=1
+    fi
     if test "$gcc_cv_ld64_major" -ge 512; then
       gcc_cv_ld64_platform_version=1
       gcc_cv_ld64_macos_version_min=1
@@ -32785,6 +32789,15 @@ $as_echo_n "checking linker for -export_dynamic support... " >&6; }
     { $as_echo "$as_me:${as_lineno-$LINENO}: result: $gcc_cv_ld64_export_dynamic" >&5
 $as_echo "$gcc_cv_ld64_export_dynamic" >&6; }
 
+    { $as_echo "$as_me:${as_lineno-$LINENO}: checking linker for -no_deduplicate support" >&5
+$as_echo_n "checking linker for -no_deduplicate support... " >&6; }
+    gcc_cv_ld64_no_deduplicate=1
+    if $gcc_cv_ld -no_deduplicate < /dev/null 2>&1 | grep 'unknown option' > /dev/null; then
+      gcc_cv_ld64_no_deduplicate=0
+    fi
+    { $as_echo "$as_me:${as_lineno-$LINENO}: result: $gcc_cv_ld64_no_deduplicate" >&5
+$as_echo "$gcc_cv_ld64_no_deduplicate" >&6; }
+
     { $as_echo "$as_me:${as_lineno-$LINENO}: checking linker for -platform_version support" >&5
 $as_echo_n "checking linker for -platform_version support... " >&6; }
     gcc_cv_ld64_platform_version=1
@@ -32826,6 +32839,12 @@ _ACEOF
 
 
 cat >>confdefs.h <<_ACEOF
+#define LD64_HAS_NO_DEDUPLICATE $gcc_cv_ld64_no_deduplicate
+_ACEOF
+
+
+
+cat >>confdefs.h <<_ACEOF
 #define LD64_HAS_PLATFORM_VERSION $gcc_cv_ld64_platform_version
 _ACEOF
 
diff --git a/gcc/configure.ac b/gcc/configure.ac
index ac1f0e9..4532c5c 100644
--- a/gcc/configure.ac
+++ b/gcc/configure.ac
@@ -6392,6 +6392,7 @@ if test x"$ld64_flag" = x"yes"; then
   gcc_cv_ld64_platform_version=0
   gcc_cv_ld64_macos_version_min=0
   gcc_cv_ld64_demangle=0
+  gcc_cv_ld64_no_deduplicate=0
 
   if test "$build" = "$host"; then
     darwin_try_test=1
@@ -6419,6 +6420,9 @@ if test x"$ld64_flag" = x"yes"; then
     if test "$gcc_cv_ld64_major" -ge 236; then
       gcc_cv_ld64_export_dynamic=1
     fi
+    if test "$gcc_cv_ld64_major" -ge 262; then
+      gcc_cv_ld64_no_deduplicate=1
+    fi
     if test "$gcc_cv_ld64_major" -ge 512; then
       gcc_cv_ld64_platform_version=1
       gcc_cv_ld64_macos_version_min=1
@@ -6447,6 +6451,13 @@ if test x"$ld64_flag" = x"yes"; then
     fi
     AC_MSG_RESULT($gcc_cv_ld64_export_dynamic)
 
+    AC_MSG_CHECKING(linker for -no_deduplicate support)
+    gcc_cv_ld64_no_deduplicate=1
+    if $gcc_cv_ld -no_deduplicate < /dev/null 2>&1 | grep 'unknown option' > /dev/null; then
+      gcc_cv_ld64_no_deduplicate=0
+    fi
+    AC_MSG_RESULT($gcc_cv_ld64_no_deduplicate)
+
     AC_MSG_CHECKING(linker for -platform_version support)
     gcc_cv_ld64_platform_version=1
     if $gcc_cv_ld -platform_version macos 10.5 0.0 < /dev/null 2>&1 | grep 'unknown option' > /dev/null; then
@@ -6473,6 +6484,9 @@ if test x"$ld64_flag" = x"yes"; then
   AC_DEFINE_UNQUOTED(LD64_HAS_EXPORT_DYNAMIC, $gcc_cv_ld64_export_dynamic,
   [Define to 1 if ld64 supports '-export_dynamic'.])
 
+  AC_DEFINE_UNQUOTED(LD64_HAS_NO_DEDUPLICATE, $gcc_cv_ld64_no_deduplicate,
+  [Define to 1 if ld64 supports '-no_deduplicate'.])
+
   AC_DEFINE_UNQUOTED(LD64_HAS_PLATFORM_VERSION, $gcc_cv_ld64_platform_version,
   [Define to 1 if ld64 supports '-platform_version'.])