sparc: Fix .udiv plt on libc

With the removal of divdi3 object from sparcv9-linux-gnu build, its
definition came from libgcc and its functions internall calls .udiv.
Since glibc also exports these symbols for compatibility reasons, it
will end up creating PLT calls internally in libc.so.

To avoid it, this patch uses the linker option --wrap to replace all
the internal libc.so .udiv calls to the wrapper __wrap_.udiv. Along
with strong alias in the udiv implementations, it makes linker do
local calls.

Checked on sparcv9-linux-gnu.

	* sysdeps/sparc/sparc32/Makefile (libc.so-gnulib): New rule.
	* sysdeps/sparc/sparc32/sparcv8/udiv.S (.udiv): Make a strong_alias
	to __wrap_.udiv.
	* sysdeps/sparc/sparc32/sparcv9/udiv.S (.udiv): Likewise.
	* sysdeps/sparc/sparc32/udiv.S (.udiv): Likewise.

diff --git a/ChangeLog b/ChangeLog
index e70ecd78631ed27eef9f2e4016702aab355fb34c..9024e62fc7e0de833a721f3ce59d5969a45d3939 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,11 @@
 2017-04-05  Adhemerval Zanella  <adhemerval.zanella@linaro.org>
 
+       * sysdeps/sparc/sparc32/Makefile (libc.so-gnulib): New rule.
+       * sysdeps/sparc/sparc32/sparcv8/udiv.S (.udiv): Make a strong_alias
+       to __wrap_.udiv.
+       * sysdeps/sparc/sparc32/sparcv9/udiv.S (.udiv): Likewise.
+       * sysdeps/sparc/sparc32/udiv.S (.udiv): Likewise.
+
        * sysdeps/i386/symbol-hacks.h: New file.
        * sysdeps/m68k/symbol-hacks.h: New file.
        * sysdeps/powerpc/powerpc32/symbol-hacks.h: New file.

diff --git a/sysdeps/sparc/sparc32/Makefile b/sysdeps/sparc/sparc32/Makefile
index da205898cf62a4226c2636420b1cd1283d3d0259..14d6e03c6f16e95ec3df96e0fbb6435bcf3cead7 100644 (file)
--- a/sysdeps/sparc/sparc32/Makefile
+++ b/sysdeps/sparc/sparc32/Makefile
@@ -47,3 +47,9 @@ $(divrem:%=$(sysdep_dir)/sparc/sparc32/%.S): $(sysdep_dir)/sparc/sparc32/divrem.
        mv -f $@-tmp $@
 
 sysdep-realclean := $(sysdep-realclean) $(divrem:%=sysdeps/sparc/sparc32/%.S)
+
+# libgcc __divdi3 and __moddi3 uses .udiv and since it is also exported by
+# libc.so linker will create PLTs for the symbol.  To avoid it we strong alias
+# the exported libc one to __wrap_.udiv and use linker option --wrap to make any
+# call to .udiv to call the wrapper symbol.
+libc.so-gnulib += -Wl,--wrap=.udiv

diff --git a/sysdeps/sparc/sparc32/sparcv8/udiv.S b/sysdeps/sparc/sparc32/sparcv8/udiv.S
index d71954351effcfa320ff89eb242dd8719bc8a032..e9cab4e4ef6206ea0caaf5b9d25ed632ca8ad099 100644 (file)
--- a/sysdeps/sparc/sparc32/sparcv8/udiv.S
+++ b/sysdeps/sparc/sparc32/sparcv8/udiv.S
@@ -13,3 +13,4 @@ ENTRY(.udiv)
         udiv   %o0, %o1, %o0
 
 END(.udiv)
+strong_alias (.udiv, __wrap_.udiv)

diff --git a/sysdeps/sparc/sparc32/sparcv9/udiv.S b/sysdeps/sparc/sparc32/sparcv9/udiv.S
index de79899756855b673c40b14ec93c3a302a27e2c5..368f85ede2c17e7ecda78210ecc5f9da62af0980 100644 (file)
--- a/sysdeps/sparc/sparc32/sparcv9/udiv.S
+++ b/sysdeps/sparc/sparc32/sparcv9/udiv.S
@@ -15,3 +15,4 @@ ENTRY(.udiv)
         udiv           %o0, %o1, %o0
 
 END(.udiv)
+strong_alias (.udiv, __wrap_.udiv)

diff --git a/sysdeps/sparc/sparc32/udiv.S b/sysdeps/sparc/sparc32/udiv.S
index 8dfff661584a19b5ae90809fe451c6dfe28746b9..ade0afdf40db33aac0648e5b3d0cfcfa67f4c0c8 100644 (file)
--- a/sysdeps/sparc/sparc32/udiv.S
+++ b/sysdeps/sparc/sparc32/udiv.S
@@ -344,3 +344,4 @@ LOC(got_result):
        mov %o2, %o0
 
 END(.udiv)
+strong_alias (.udiv, __wrap_.udiv)