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[PATCH] Fix up -fdwarf2-cfi-asm on ppc/ppc64


Hi!

While working on unwind info for epilogues for rs6000, I've noticed that
-fdwarf2-cfi-asm vs. -fno-dwarf2-cfi-asm generated .eh_frame substantially
differs, e.g. when noting the location of saved cr (after mfcr 12),
-fno-dwarf2-cfi-asm has DW_CFA_register: r70 in r12, while
-fdwarf2-cfi-asm has DW_CFA_register: r64 in r12.  Seems weird nobody
reported this yet.  After further investigation it seems ppc uses different
register numbering for .eh_frame and .dwarf_frame.  Given that .cfi_*
directives generate .eh_frame section, not .dwarf_frame, we should use
register numbers for .eh_frame, not for .dwarf_frame.  The patch below
should have no effect except on powerpc* (where it should fix this) and
on i?86-darwin (where gas isn't used and thus output_cfi_directive isn't
ever used).

I'll bootstrap/regtest later tonight, if that passes, is this ok for
trunk/4.4 (given that it is pretty severe ABI issue)?

2009-06-02  Jakub Jelinek  <jakub@redhat.com>

	* dwarf2out.c (output_cfi_directive): Pass 1 instead of
	0 to second argument of DWARF2_FRAME_REG_OUT macros.

--- gcc/dwarf2out.c.jj	2009-06-01 12:32:55.000000000 +0200
+++ gcc/dwarf2out.c	2009-06-02 14:50:03.000000000 +0200
@@ -3089,42 +3089,42 @@ output_cfi_directive (dw_cfi_ref cfi)
     case DW_CFA_offset:
     case DW_CFA_offset_extended:
     case DW_CFA_offset_extended_sf:
-      r = DWARF2_FRAME_REG_OUT (cfi->dw_cfi_oprnd1.dw_cfi_reg_num, 0);
+      r = DWARF2_FRAME_REG_OUT (cfi->dw_cfi_oprnd1.dw_cfi_reg_num, 1);
       fprintf (asm_out_file, "\t.cfi_offset %lu, "HOST_WIDE_INT_PRINT_DEC"\n",
 	       r, cfi->dw_cfi_oprnd2.dw_cfi_offset);
       break;
 
     case DW_CFA_restore:
     case DW_CFA_restore_extended:
-      r = DWARF2_FRAME_REG_OUT (cfi->dw_cfi_oprnd1.dw_cfi_reg_num, 0);
+      r = DWARF2_FRAME_REG_OUT (cfi->dw_cfi_oprnd1.dw_cfi_reg_num, 1);
       fprintf (asm_out_file, "\t.cfi_restore %lu\n", r);
       break;
 
     case DW_CFA_undefined:
-      r = DWARF2_FRAME_REG_OUT (cfi->dw_cfi_oprnd1.dw_cfi_reg_num, 0);
+      r = DWARF2_FRAME_REG_OUT (cfi->dw_cfi_oprnd1.dw_cfi_reg_num, 1);
       fprintf (asm_out_file, "\t.cfi_undefined %lu\n", r);
       break;
 
     case DW_CFA_same_value:
-      r = DWARF2_FRAME_REG_OUT (cfi->dw_cfi_oprnd1.dw_cfi_reg_num, 0);
+      r = DWARF2_FRAME_REG_OUT (cfi->dw_cfi_oprnd1.dw_cfi_reg_num, 1);
       fprintf (asm_out_file, "\t.cfi_same_value %lu\n", r);
       break;
 
     case DW_CFA_def_cfa:
     case DW_CFA_def_cfa_sf:
-      r = DWARF2_FRAME_REG_OUT (cfi->dw_cfi_oprnd1.dw_cfi_reg_num, 0);
+      r = DWARF2_FRAME_REG_OUT (cfi->dw_cfi_oprnd1.dw_cfi_reg_num, 1);
       fprintf (asm_out_file, "\t.cfi_def_cfa %lu, "HOST_WIDE_INT_PRINT_DEC"\n",
 	       r, cfi->dw_cfi_oprnd2.dw_cfi_offset);
       break;
 
     case DW_CFA_def_cfa_register:
-      r = DWARF2_FRAME_REG_OUT (cfi->dw_cfi_oprnd1.dw_cfi_reg_num, 0);
+      r = DWARF2_FRAME_REG_OUT (cfi->dw_cfi_oprnd1.dw_cfi_reg_num, 1);
       fprintf (asm_out_file, "\t.cfi_def_cfa_register %lu\n", r);
       break;
 
     case DW_CFA_register:
-      r = DWARF2_FRAME_REG_OUT (cfi->dw_cfi_oprnd1.dw_cfi_reg_num, 0);
-      r2 = DWARF2_FRAME_REG_OUT (cfi->dw_cfi_oprnd2.dw_cfi_reg_num, 0);
+      r = DWARF2_FRAME_REG_OUT (cfi->dw_cfi_oprnd1.dw_cfi_reg_num, 1);
+      r2 = DWARF2_FRAME_REG_OUT (cfi->dw_cfi_oprnd2.dw_cfi_reg_num, 1);
       fprintf (asm_out_file, "\t.cfi_register %lu, %lu\n", r, r2);
       break;
 

	Jakub


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