collect2.c (DO_COLLECT_EXPORT_LIST): New internal macro, always defined.

        * collect2.c (DO_COLLECT_EXPORT_LIST): New internal macro,
        always defined.  Reflect definition or absence of such for
        COLLECT_EXPORT_LIST.  Readability helper.
        (scanfilter): New enum, to help control what symbols
        are to be considered or ignored by scan_prog_file.
        (enum pass): Rename as "scanpass", moved together with scanfilter
        prior to scan_prog_file's prototype.
        (scan_prog_file): Accept and honor scanpass and scanfilter arguments.
        Group prototype with the scanpass/scanfilter definitions, factorize
        head comments for the several implementations at the prototype.
        (main): Reorganize the first pass link control to let AIX
        drag only the needed frame tables in executables.  Prevent
        frame tables collection during the scan aimed at static ctors.
        Pre-link and scan for frame tables later to compensate.
        * doc/tm.texi (ASM_OUTPUT_DWARF_TABLE_REF): New macro.
        A C statement to issue assembly directives that create a reference
        to the given DWARF table identifier label from the current function
        section.
        * dwarf2out.c (switch_to_eh_frame_section): Add a BACK argument
        to differentiate first time section entry.  Only emit a .data
        tables start identifier label the first time around.
        (switch_to_frame_table_section): New function.  Helper for
        output_call_frame_info to switch possibly BACK into the eh_frame
        or the debug_frame section depending on FOR_EH.
        (output_call_frame_info): Use helper to first enter the proper
        frame section.
        (output_fde): Use ASM_OUTPUT_DWARF_TABLE_REF when defined to
        emit a link to the frame table start label from each function
        section.
        * config/rs6000/rs6000.c (rs6000_aix_asm_output_dwarf_table_ref):
        New function.  Implementation of ASM_OUTPUT_DWARF_TABLE_REF.
        * config/rs6000/rs6000-protos.h: Declare it.
        * config/rs6000/aix.h (ASM_OUTPUT_DWARF_TABLE_REF): Define.

From-SVN: r151157

3 files changed, 17 insertions, 0 deletions

diff --git a/gcc/config/rs6000/aix.h b/gcc/config/rs6000/aix.h
index 44015a3..4676110 100644
--- a/gcc/config/rs6000/aix.h
+++ b/gcc/config/rs6000/aix.h
@@ -43,6 +43,12 @@
    collect has a chance to see them, so scan the object files directly.  */
 #define COLLECT_EXPORT_LIST
 
+/* Issue assembly directives that create a reference to the given DWARF table
+   identifier label from the current function section.  This is defined to
+   ensure we drag frame frame tables associated with needed function bodies in
+   a link with garbage collection activated.  */
+#define ASM_OUTPUT_DWARF_TABLE_REF rs6000_aix_asm_output_dwarf_table_ref
+
 /* Handle #pragma weak and #pragma pack.  */
 #define HANDLE_SYSV_PRAGMA 1
 
diff --git a/gcc/config/rs6000/rs6000-protos.h b/gcc/config/rs6000/rs6000-protos.h
index 96f215b..6e6bb9e 100644
--- a/gcc/config/rs6000/rs6000-protos.h
+++ b/gcc/config/rs6000/rs6000-protos.h
@@ -179,6 +179,8 @@ extern int rs6000_memory_move_cost (enum machine_mode, enum reg_class, int);
 extern bool rs6000_tls_referenced_p (rtx);
 extern void rs6000_conditional_register_usage (void);
 
+extern void rs6000_aix_asm_output_dwarf_table_ref (char *);
+
 /* Declare functions in rs6000-c.c */
 
 extern void rs6000_pragma_longcall (struct cpp_reader *);
diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index cb64d28..8e31cbb 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -17612,6 +17612,15 @@ create_TOC_reference (rtx symbol)
 	       gen_rtx_UNSPEC (Pmode, gen_rtvec (1, symbol), UNSPEC_TOCREL)));
 }
 
+/* Issue assembly directives that create a reference to the given DWARF
+   FRAME_TABLE_LABEL from the current function section.  */
+void
+rs6000_aix_asm_output_dwarf_table_ref (char * frame_table_label)
+{
+  fprintf (asm_out_file, "\t.ref %s\n",
+	   TARGET_STRIP_NAME_ENCODING (frame_table_label));
+}
+
 /* If _Unwind_* has been called from within the same module,
    toc register is not guaranteed to be saved to 40(1) on function
    entry.  Save it there in that case.  */