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-rw-r--r--gdb/symtab.c54
1 files changed, 54 insertions, 0 deletions
diff --git a/gdb/symtab.c b/gdb/symtab.c
index 622e277..99f138a 100644
--- a/gdb/symtab.c
+++ b/gdb/symtab.c
@@ -3860,6 +3860,60 @@ in_prologue (CORE_ADDR pc, CORE_ADDR func_start)
return func_addr <= pc && pc < sal.end;
}
+/* Given PC at the function's start address, attempt to find the
+ prologue end using SAL information. Return zero if the skip fails.
+
+ A non-optimized prologue traditionally has one SAL for the function
+ and a second for the function body. A single line function has
+ them both pointing at the same line.
+
+ An optimized prologue is similar but the prologue may contain
+ instructions (SALs) from the instruction body. Need to skip those
+ while not getting into the function body.
+
+ The functions end point and an increasing SAL line are used as
+ indicators of the prologue's endpoint.
+
+ This code is based on the function refine_prologue_limit (versions
+ found in both ia64 and ppc). */
+
+CORE_ADDR
+skip_prologue_using_sal (CORE_ADDR func_addr)
+{
+ struct symtab_and_line prologue_sal;
+ CORE_ADDR start_pc;
+ CORE_ADDR end_pc;
+
+ /* Get an initial range for the function. */
+ find_pc_partial_function (func_addr, NULL, &start_pc, &end_pc);
+ start_pc += FUNCTION_START_OFFSET;
+
+ prologue_sal = find_pc_line (start_pc, 0);
+ if (prologue_sal.line != 0)
+ {
+ while (prologue_sal.end < end_pc)
+ {
+ struct symtab_and_line sal;
+
+ sal = find_pc_line (prologue_sal.end, 0);
+ if (sal.line == 0)
+ break;
+ /* Assume that a consecutive SAL for the same (or larger)
+ line mark the prologue -> body transition. */
+ if (sal.line >= prologue_sal.line)
+ break;
+ /* The case in which compiler's optimizer/scheduler has
+ moved instructions into the prologue. We look ahead in
+ the function looking for address ranges whose
+ corresponding line number is less the first one that we
+ found for the function. This is more conservative then
+ refine_prologue_limit which scans a large number of SALs
+ looking for any in the prologue */
+ prologue_sal = sal;
+ }
+ }
+ return prologue_sal.end;
+}
struct symtabs_and_lines
decode_line_spec (char *string, int funfirstline)