Also, remove the "fix" to DW_CFA_def_cfa_register where we reset the
frame's cfa_offset to 0. This action is incorrect when handling
DW_CFA_def_cfa_register as the DWARF spec specifically states that the
previous contents of cfa_offset should be used with the new
register. The reason that I thought cfa_offset should be reset to 0 was
because it was being assigned a bogus value prior to executing the
DW_CFA_def_cfa_register op. It turns out that the bogus cfa_offset value
came from interpreting .cfi_escape pseudo-ops (those used by the GNU
extensions) as CFA_DW_def_cfa ops.
Signed-off-by: Matt Fleming <matt@console-pimps.org>
#define DW_CFA_lo_user 0x1c
#define DW_CFA_hi_user 0x3f
#define DW_CFA_lo_user 0x1c
#define DW_CFA_hi_user 0x3f
+/* GNU extension opcodes */
+#define DW_CFA_GNU_args_size 0x2e
+#define DW_CFA_GNU_negative_offset_extended 0x2f
+
/*
* Some call frame instructions encode their operands in the opcode. We
* need some helper functions to extract both the opcode and operands
/*
* Some call frame instructions encode their operands in the opcode. We
* need some helper functions to extract both the opcode and operands
count = dwarf_read_uleb128(current_insn,
&frame->cfa_register);
current_insn += count;
count = dwarf_read_uleb128(current_insn,
&frame->cfa_register);
current_insn += count;
frame->flags |= DWARF_FRAME_CFA_REG_OFFSET;
break;
case DW_CFA_def_cfa_offset:
frame->flags |= DWARF_FRAME_CFA_REG_OFFSET;
break;
case DW_CFA_def_cfa_offset:
frame->regs[reg].flags |= DWARF_REG_OFFSET;
frame->regs[reg].addr = offset;
break;
frame->regs[reg].flags |= DWARF_REG_OFFSET;
frame->regs[reg].addr = offset;
break;
+ case DW_CFA_GNU_args_size:
+ count = dwarf_read_uleb128(current_insn, &offset);
+ current_insn += count;
+ break;
+ case DW_CFA_GNU_negative_offset_extended:
+ count = dwarf_read_uleb128(current_insn, ®);
+ current_insn += count;
+ count = dwarf_read_uleb128(current_insn, &offset);
+ offset *= cie->data_alignment_factor;
+ dwarf_frame_alloc_regs(frame, reg);
+ frame->regs[reg].flags |= DWARF_REG_OFFSET;
+ frame->regs[reg].addr = -offset;
+ break;
default:
pr_debug("unhandled DWARF instruction 0x%x\n", insn);
break;
default:
pr_debug("unhandled DWARF instruction 0x%x\n", insn);
break;