diff mbox

Handle __gmon_start__ as undefined weak or hidden on hppa

Message ID BBB983E5-87CC-4BED-967E-2C6A90DE120F@bell.net
State Superseded
Headers show

Commit Message

John David Anglin Oct. 25, 2015, 7:32 p.m. UTC
The attached change fixes libc/19170.  It is identical to the approach used on ia64 aside from
the hppa assembler code.

It has been build tested on trunk and with Debian 2.19.  It resolves the harfbuzz issue noted in
the PR.

Please install if okay.

Dave
--
John David Anglin	dave.anglin@bell.net
2015-10-25  Helge Deller  <deller@gmx.de>
	    John David Anglin  <danglin@gcc.gnu.org>

	PR libc/19170
	* sysdeps/hppa/crti.S (gmon_initializer): New.  Use .init_array support
	to call gmon_initializer.  Only call __gmon_start__ when symbol is
	defined.
	* sysdeps/hppa/crtn.S (__gmon_start__): Delete.
diff mbox

Patch

diff -up ./crti.S.org ./crti.S
--- ./crti.S.org	2015-10-23 17:46:33.115387971 +0200
+++ ./crti.S	2015-10-23 21:46:25.277880769 +0200
@@ -49,6 +49,72 @@ 
 # define PREINIT_FUNCTION_WEAK 1
 #endif
 
+#if PREINIT_FUNCTION_WEAK
+	weak_extern (PREINIT_FUNCTION)
+#else
+	.hidden PREINIT_FUNCTION
+#endif
+
+
+/* If we have working .init_array support, we want to keep the .init
+   section empty (apart from the mandatory prologue/epilogue.  This
+   ensures that the default unwind conventions (return-pointer in b0,
+   frame state in ar.pfs, etc.)  will do the Right Thing.  To ensure
+   an empty .init section, we register gmon_initializer() via the
+   .init_array.
+
+    --davidm 02/10/29 */
+
+#if PREINIT_FUNCTION_WEAK
+/* This blob of assembly code is one simple C function:
+
+static void
+__attribute__ ((used))
+gmon_initializer (void)
+{
+  extern void weak_function __gmon_start__ (void);
+
+  if (__gmon_start__)
+    (*__gmon_start__)();
+}
+*/
+        .section        .data.rel.ro,"aw",@progbits
+        .align 4
+.LC0:
+        .word   P%__gmon_start__
+        .text
+        .align 4
+        .type   gmon_initializer, @function
+gmon_initializer:
+        .PROC
+        .CALLINFO FRAME=64,CALLS,SAVE_RP,ENTRY_GR=3
+        .ENTRY
+        stw %r2,-20(%r30)
+        addil LT'.LC0,%r19
+        ldw RT'.LC0(%r1),%r28
+        stwm %r4,64(%r30)
+        ldw 0(%r28),%r28
+        comib,= 0,%r28,.L1
+        stw %r19,-32(%r30)
+        bl __gmon_start__,%r2
+        nop
+.L1:
+        ldw -84(%r30),%r2
+        bv %r0(%r2)
+        ldwm -64(%r30),%r4
+        .EXIT
+        .PROCEND
+
+        .size   gmon_initializer, .-gmon_initializer
+
+# undef PREINIT_FUNCTION
+# define PREINIT_FUNCTION gmon_initializer
+#endif
+
+        .section .init_array, "aw"
+        .word P% PREINIT_FUNCTION
+
+
 /* _init prologue.  */
 	.section .init, "ax", %progbits
 	.align 4
@@ -58,14 +124,6 @@  _init:
 	stw	%rp,-20(%sp)
 	stwm	%r4,64(%sp)
 	stw	%r19,-32(%sp)
-#if PREINIT_FUNCTION_WEAK
-	bl	PREINIT_FUNCTION,%rp
-	copy	%r19,%r4	/* delay slot */
-#else
-	bl	PREINIT_FUNCTION,%rp
-	copy	%r19,%r4	/* delay slot */
-#endif
-	copy	%r4,%r19
 
 /* _fini prologue.  */
         .section .fini,"ax",%progbits
diff -up ./crtn.S.org ./crtn.S
--- ./crtn.S.org	2015-10-23 17:46:28.283390160 +0200
+++ ./crtn.S	2015-10-23 17:47:15.691368693 +0200
@@ -38,27 +38,6 @@ 
 /* crtn.S puts function epilogues in the .init and .fini sections
    corresponding to the prologues in crti.S. */
 
-/* Note that we cannot have a weak undefined __gmon_start__, because
-   that would require this to be PIC, and the linker is currently not
-   able to generate a proper procedure descriptor for _init.  Sad but
-   true.  Anyway, HPPA is one of those horrible architectures where
-   making the comparison and indirect call is quite expensive (see the
-   comment in sysdeps/generic/initfini.c). */
-        .text
-        .align 4
-        .weak   __gmon_start__
-        .type    __gmon_start__,@function
-__gmon_start__:
-	.proc
-	.callinfo
-	.entry
-        bv,n %r0(%r2)
-	.exit
-	.procend
-
-/* Here is the tail end of _init.  We put __gmon_start before this so
-   that the assembler creates the .PARISC.unwind section for us, ie.
-   with the right attributes.  */
 	.section .init, "ax", @progbits
 	ldw	-84(%sp),%rp
 	copy	%r4,%r19