pa.c (pa_output_addr_vec): Align address table.

	* config/pa/pa.c (pa_output_addr_vec): Align address table.
	* config/pa/pa.h (JUMP_TABLES_IN_TEXT_SECTION): Revise comment.
	* config/pa/pa32-linux.h (JUMP_TABLES_IN_TEXT_SECTION): Define.

From-SVN: r263051

4 files changed, 29 insertions, 10 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index cc27dbc..9d70b46 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2018-07-29  John David Anglin  <danglin@gcc.gnu.org>
+
+	* config/pa/pa.c (pa_output_addr_vec): Align address table.
+	* config/pa/pa.h (JUMP_TABLES_IN_TEXT_SECTION): Revise comment.
+	* config/pa/pa32-linux.h (JUMP_TABLES_IN_TEXT_SECTION): Define.
+
 2018-07-27  Michael Meissner  <meissner@linux.ibm.com>
 
 	* config/rs6000/constraints.md (wG constraint): Delete, no longer
diff --git a/gcc/config/pa/pa.c b/gcc/config/pa/pa.c
index a32921a..715700e 100644
--- a/gcc/config/pa/pa.c
+++ b/gcc/config/pa/pa.c
@@ -10680,6 +10680,8 @@ pa_output_addr_vec (rtx lab, rtx body)
 {
   int idx, vlen = XVECLEN (body, 0);
 
+  if (!TARGET_SOM)
+    fputs ("\t.align 4\n", asm_out_file);
   targetm.asm_out.internal_label (asm_out_file, "L", CODE_LABEL_NUMBER (lab));
   if (TARGET_GAS)
     fputs ("\t.begin_brtab\n", asm_out_file);
diff --git a/gcc/config/pa/pa.h b/gcc/config/pa/pa.h
index 024e7b8..a121e20 100644
--- a/gcc/config/pa/pa.h
+++ b/gcc/config/pa/pa.h
@@ -1143,21 +1143,23 @@ do {									     \
 #define ASM_OUTPUT_ASCII(FILE, P, SIZE)  \
   pa_output_ascii ((FILE), (P), (SIZE))
 
-/* Jump tables are always placed in the text section.  Technically, it
-   is possible to put them in the readonly data section.  This has the
-   benefit of getting the table out of .text and reducing branch lengths
-   as a result.
+/* Jump tables are always placed in the text section.  We have to do
+   this for the HP-UX SOM target as we can't switch sections in the
+   middle of a function.
 
-   The downside is that an additional insn (addil) is needed to access
+   On ELF targets, it is possible to put them in the readonly-data section.
+   This would get the table out of .text and reduce branch lengths.
+
+   A downside is that an additional insn (addil) is needed to access
    the table when generating PIC code.  The address difference table
-   also has to use 32-bit pc-relative relocations.  Currently, GAS does
-   not support these relocations, although it is easily modified to do
-   this operation.
+   also has to use 32-bit pc-relative relocations.
 
    The table entries need to look like "$L1+(.+8-$L0)-$PIC_pcrel$0"
    when using ELF GAS.  A simple difference can be used when using
-   SOM GAS or the HP assembler.  The final downside is GDB complains
-   about the nesting of the label for the table when debugging.  */
+   the HP assembler.
+
+   The final downside is GDB complains about the nesting of the label
+   for the table.  */
 
 #define JUMP_TABLES_IN_TEXT_SECTION 1
 
diff --git a/gcc/config/pa/pa32-linux.h b/gcc/config/pa/pa32-linux.h
index ffcd1c6..4b47044 100644
--- a/gcc/config/pa/pa32-linux.h
+++ b/gcc/config/pa/pa32-linux.h
@@ -67,3 +67,12 @@ call_ ## FUNC (void)					\
    layout compatibility with the original linux thread implementation.  */
 #undef MALLOC_ABI_ALIGNMENT
 #define MALLOC_ABI_ALIGNMENT 128
+
+/* Place jump tables in the text section except when generating non-PIC
+   code.  When generating non-PIC code, the relocations needed to load the
+   address of the jump table result in a text label in the final executable
+   if the jump table is placed in the text section.  This breaks the unwind
+   data for the function.  Thus, the jump table needs to be placed in
+   rodata when generating non-PIC code.  */
+#undef JUMP_TABLES_IN_TEXT_SECTION
+#define JUMP_TABLES_IN_TEXT_SECTION (flag_pic)