[gcc r11-11365] Darwin: Match system sections and relocs for exception tables.

[gcc r11-11365] Darwin: Match system sections and relocs for exception tables.

[Iain D Sandoe]

https://gcc.gnu.org/g:9488ad0d780fae91afa910410cb4e6da8d607fd9

commit r11-11365-g9488ad0d780fae91afa910410cb4e6da8d607fd9
Author: Iain Sandoe <iain@sandoe.co.uk>
Date:   Thu Aug 31 19:20:43 2023 +0100

    Darwin: Match system sections and relocs for exception tables.
    
    System tools from Darwin10 onwards have moved the exceptions tables from
    the __DATA segment to the __TEXT one.  They also revised the relocations
    used for typeinfo.  While Darwin9 was not changed at the time, in fact the
    tools there are equally happy with the revised scheme - and therefore at
    present there seems no reason to special-case it.
    
    Signed-off-by: Iain Sandoe <iain@sandoe.co.uk>
    
    gcc/ChangeLog:
    
            * config/darwin-sections.def (darwin_exception_section): Move to
            the __TEXT segment.
            * config/darwin.c (darwin_emit_except_table_label): Align before
            the exception table label.
            * config/darwin.h (ASM_PREFERRED_EH_DATA_FORMAT): Use indirect PC-
            relative 4byte relocs.
    
    (cherry picked from commit 0fe7962afc7c01488432b98b6f442b24946a490d)

Diff:
---
 gcc/config/darwin-sections.def | 2 +-
 gcc/config/darwin.c            | 1 +
 gcc/config/darwin.h            | 2 +-
 3 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/gcc/config/darwin-sections.def b/gcc/config/darwin-sections.def
index 8be89624c9c..ed9e058d1d1 100644
--- a/gcc/config/darwin-sections.def
+++ b/gcc/config/darwin-sections.def
@@ -157,7 +157,7 @@ DEF_SECTION (machopic_picsymbol_stub3_section, SECTION_NO_ANCHOR,
 
 /* Exception-related.  */
 DEF_SECTION (darwin_exception_section, SECTION_NO_ANCHOR,
-	     ".section __DATA,__gcc_except_tab", 0)
+	     ".section __TEXT,__gcc_except_tab", 0)
 DEF_SECTION (darwin_eh_frame_section, SECTION_NO_ANCHOR,
 	     ".section " EH_FRAME_SECTION_NAME ",__eh_frame"
 	     EH_FRAME_SECTION_ATTR, 0)
diff --git a/gcc/config/darwin.c b/gcc/config/darwin.c
index 2371816e251..ddbd3943a1d 100644
--- a/gcc/config/darwin.c
+++ b/gcc/config/darwin.c
@@ -2230,6 +2230,7 @@ darwin_emit_except_table_label (FILE *file)
 {
   char section_start_label[30];
 
+  fputs ("\t.p2align\t2\n", file);
   ASM_GENERATE_INTERNAL_LABEL (section_start_label, "GCC_except_table",
 			       except_table_label_num++);
   ASM_OUTPUT_LABEL (file, section_start_label);
diff --git a/gcc/config/darwin.h b/gcc/config/darwin.h
index 5be13293319..9cae0165ae9 100644
--- a/gcc/config/darwin.h
+++ b/gcc/config/darwin.h
@@ -1098,7 +1098,7 @@ enum machopic_addr_class {
 
 #undef ASM_PREFERRED_EH_DATA_FORMAT
 #define ASM_PREFERRED_EH_DATA_FORMAT(CODE,GLOBAL)  \
-  (((CODE) == 2 && (GLOBAL) == 1) \
+  (((CODE) == 2 && (GLOBAL) == 1) || ((CODE) == 0 && (GLOBAL) == 1) \
    ? (DW_EH_PE_pcrel | DW_EH_PE_indirect | DW_EH_PE_sdata4) : \
      ((CODE) == 1 || (GLOBAL) == 0) ? DW_EH_PE_pcrel : DW_EH_PE_absptr)