Merge patch from JosefW:

Hi,

recently I found that there is sometimes cost attributed to some
strange lines (with cachegrind/calltree) with GCC 3.x (using the
DWARF2 debug info format).

I had time to look at this. There is a bug in the DWARF2 debug line
info loader when instructions following each other have source lines
far from each other (e.g. with inlined functions).

MERGE TO STABLE

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@1619

diff --git a/coregrind/vg_symtab2.c b/coregrind/vg_symtab2.c
index b11b1c2f51f2bbba734adff0ca099cc681d1fb94..304e9b97c0310403e7b67a8b6c4a7dd54326b796 100644 (file)
--- a/coregrind/vg_symtab2.c
+++ b/coregrind/vg_symtab2.c
@@ -925,12 +925,13 @@ enum dwarf_line_number_x_ops
 
 typedef struct State_Machine_Registers
 {
-  Addr  address;
-  /* Holds the address of the last statement boundary.
-   * We use it to calculate statement lengths. Without it,
-   * we would need to search backwards for last statement begin
-   * each time we are emitting a statement with addLineInfo */
+  /* Information for the last statement boundary.
+   * Needed to calculate statement lengths. */
   Addr  last_address;
+  UInt  last_file;
+  UInt  last_line;
+
+  Addr  address;
   UInt  file;
   UInt  line;
   UInt  column;
@@ -979,8 +980,10 @@ static
 void reset_state_machine ( Int is_stmt )
 {
   if (0) VG_(printf)("smr.a := %p (reset)\n", 0 );
-  state_machine_regs.address = 0;
   state_machine_regs.last_address = 0;
+  state_machine_regs.last_file = 1;
+  state_machine_regs.last_line = 1;
+  state_machine_regs.address = 0;
   state_machine_regs.file = 1;
   state_machine_regs.line = 1;
   state_machine_regs.column = 0;
@@ -1027,10 +1030,10 @@ int process_extended_line_op( SegInfo *si, UInt** fnames,
       */
       if (state_machine_regs.is_stmt) {
          if (state_machine_regs.last_address)
-             addLineInfo (si, (*fnames)[state_machine_regs.file], 
+             addLineInfo (si, (*fnames)[state_machine_regs.last_file], 
                        si->offset + state_machine_regs.last_address, 
                        si->offset + state_machine_regs.address, 
-                       state_machine_regs.line, 0);
+                       state_machine_regs.last_line, 0);
       }
       reset_state_machine (is_stmt);
       break;
@@ -1249,16 +1252,19 @@ void read_debuginfo_dwarf2 ( SegInfo* si, UChar* dwarf2, Int dwarf2_sz )
              adv = (op_code % info.li_line_range) + info.li_line_base;
              if (0) VG_(printf)("1002: si->o %p, smr.a %p\n", 
                                 si->offset, state_machine_regs.address );
+             state_machine_regs.line += adv;
+
             if (state_machine_regs.is_stmt) {
                 /* only add a statement if there was a previous boundary */
                 if (state_machine_regs.last_address) 
-                    addLineInfo (si, fnames[state_machine_regs.file], 
+                    addLineInfo (si, fnames[state_machine_regs.last_file], 
                              si->offset + state_machine_regs.last_address, 
                               si->offset + state_machine_regs.address, 
-                              state_machine_regs.line, 0);
+                              state_machine_regs.last_line, 0);
                 state_machine_regs.last_address = state_machine_regs.address;
+                state_machine_regs.last_file = state_machine_regs.file;
+                state_machine_regs.last_line = state_machine_regs.line;
             }
-             state_machine_regs.line += adv;
            }
          else switch (op_code)
            {
@@ -1274,11 +1280,13 @@ void read_debuginfo_dwarf2 ( SegInfo* si, UChar* dwarf2, Int dwarf2_sz )
             if (state_machine_regs.is_stmt) {
                 /* only add a statement if there was a previous boundary */
                 if (state_machine_regs.last_address) 
-                    addLineInfo (si, fnames[state_machine_regs.file], 
+                    addLineInfo (si, fnames[state_machine_regs.last_file], 
                               si->offset + state_machine_regs.last_address, 
                               si->offset + state_machine_regs.address,
-                              state_machine_regs.line , 0);
+                              state_machine_regs.last_line , 0);
                 state_machine_regs.last_address = state_machine_regs.address;
+                state_machine_regs.last_file = state_machine_regs.file;
+                state_machine_regs.last_line = state_machine_regs.line;
             }
              state_machine_regs.basic_block = 0; /* JRS added */
              break;