readdwarf3: Reuse fndn_ix_Table as much as possible

Both the var parser and the inl parser kept a fndn_ix_Table.
Initialize only one per debuginfo read pass and reuse if the stmt offset
is the same as last time (CUs can share the same line table and alt
files do share one for all units).

diff --git a/coregrind/m_debuginfo/readdwarf3.c b/coregrind/m_debuginfo/readdwarf3.c
index 7ece770090998063cb3e446e8ad77939efbba7cd..e63e357881139005be6a0b3703b76a498b8b3b56 100644 (file)
--- a/coregrind/m_debuginfo/readdwarf3.c
+++ b/coregrind/m_debuginfo/readdwarf3.c
@@ -1801,9 +1801,6 @@ typedef
       Int     *level;  /* D3 DIE levels */
       Bool    *isFunc; /* from DW_AT_subprogram? */
       GExpr  **fbGX;   /* if isFunc, contains the FB expr, else NULL */
-      /* The fndn_ix file name/dirname table.  Is a mapping from dwarf
-         integer index to the index in di->fndnpool. */
-      XArray* /* of UInt* */ fndn_ix_Table;
    }
    D3VarParser;
 
@@ -1817,7 +1814,6 @@ var_parser_init ( D3VarParser *parser )
    parser->level  = NULL;
    parser->isFunc = NULL;
    parser->fbGX = NULL;
-   parser->fndn_ix_Table = NULL;
 }
 
 /* Release any memory hanging off a variable parser object */
@@ -2471,12 +2467,39 @@ static void bad_DIE_confusion(int linenr)
 }
 #define goto_bad_DIE do {bad_DIE_confusion(__LINE__); goto bad_DIE;} while (0)
 
+/* Reset the fndn_ix_Table.  When we come across the top level DIE for a CU we
+   will copy all the file names out of the .debug_line img area and use this
+   table to look up the copies when we later see filename numbers in
+   DW_TAG_variables etc. The table can be be reused between parsers (var and
+   inline) and between CUs. So we keep a copy of the last one parsed. Call
+   reset_fndn_ix_table before reading a new one from a new offset.  */
+static
+void reset_fndn_ix_table (XArray** fndn_ix_Table, ULong *debug_line_offset,
+                          ULong new_offset)
+{
+   vg_assert (new_offset == -1
+              || *debug_line_offset != new_offset);
+   Int size = *fndn_ix_Table == NULL ? 0 : VG_(sizeXA) (*fndn_ix_Table);
+   if (size > 0) {
+      VG_(deleteXA) (*fndn_ix_Table);
+      *fndn_ix_Table = NULL;
+   }
+   if (*fndn_ix_Table == NULL)
+      *fndn_ix_Table = VG_(newXA)( ML_(dinfo_zalloc),
+                                   "di.readdwarf3.reset_ix_table",
+                                   ML_(dinfo_free),
+                                   sizeof(UInt) );
+   *debug_line_offset = new_offset;
+}
+
 __attribute__((noinline))
 static void parse_var_DIE (
    /*MOD*/WordFM* /* of (XArray* of AddrRange, void) */ rangestree,
    /*MOD*/XArray* /* of TempVar* */ tempvars,
    /*MOD*/XArray* /* of GExpr* */ gexprs,
    /*MOD*/D3VarParser* parser,
+   XArray** fndn_ix_Table,
+   ULong *debug_line_offset,
    DW_TAG dtag,
    UWord posn,
    Int level,
@@ -2535,8 +2558,12 @@ static void parse_var_DIE (
             ML_(dinfo_free) (str);
          }
          if (attr == DW_AT_stmt_list && cts.szB > 0) {
-            read_filename_table( parser->fndn_ix_Table, compdir,
-                                 cc, cts.u.val, td3 );
+            if (cts.u.val != *debug_line_offset) {
+               reset_fndn_ix_table( fndn_ix_Table, debug_line_offset,
+                                    cts.u.val );
+               read_filename_table( *fndn_ix_Table, compdir,
+                                    cc, cts.u.val, td3 );
+            }
          }
       }
       if (have_lo && have_hi1 && hiIsRelative)
@@ -2730,8 +2757,8 @@ static void parse_var_DIE (
          if (attr == DW_AT_decl_file && cts.szB > 0) {
             Int ftabIx = (Int)cts.u.val;
             if (ftabIx >= 1
-                && ftabIx < VG_(sizeXA)( parser->fndn_ix_Table )) {
-               fndn_ix = *(UInt*)VG_(indexXA)( parser->fndn_ix_Table, ftabIx );
+                && ftabIx < VG_(sizeXA)( *fndn_ix_Table )) {
+               fndn_ix = *(UInt*)VG_(indexXA)( *fndn_ix_Table, ftabIx );
             }
             if (0) VG_(printf)("XXX filename fndn_ix = %u %s\n", fndn_ix,
                                ML_(fndn_ix2filename) (cc->di, fndn_ix));
@@ -2958,9 +2985,6 @@ static void parse_var_DIE (
 
 typedef
    struct {
-      /* The fndn_ix file name/dirname table.  Is a mapping from dwarf
-         integer index to the index in di->fndnpool. */
-      XArray* /* of UInt* */ fndn_ix_Table;
       UWord sibling; // sibling of the last read DIE (if it has a sibling).
    }
    D3InlParser;
@@ -3113,6 +3137,8 @@ static const HChar* get_inlFnName (Int absori, const CUConst* cc, Bool td3)
 __attribute__((noinline))
 static Bool parse_inl_DIE (
    /*MOD*/D3InlParser* parser,
+   XArray** fndn_ix_Table,
+   ULong *debug_line_offset,
    DW_TAG dtag,
    UWord posn,
    Int level,
@@ -3135,7 +3161,7 @@ static Bool parse_inl_DIE (
       Addr ip_lo    = 0;
       const HChar *compdir = NULL;
       Bool has_stmt_list = False;
-      ULong debug_line_offset = 0;
+      ULong cu_line_offset = 0;
 
       nf_i = 0;
       while (True) {
@@ -3162,7 +3188,7 @@ static Bool parse_inl_DIE (
          }
          if (attr == DW_AT_stmt_list && cts.szB > 0) {
            has_stmt_list = True;
-            debug_line_offset = cts.u.val;
+            cu_line_offset = cts.u.val;
          }
          if (attr == DW_AT_sibling && cts.szB > 0) {
             parser->sibling = cts.u.val;
@@ -3170,9 +3196,13 @@ static Bool parse_inl_DIE (
       }
       if (level == 0) {
          setup_cu_svma (cc, have_lo, ip_lo, td3);
-         if (has_stmt_list && unit_has_addrs)
-            read_filename_table( parser->fndn_ix_Table, compdir,
-                                 cc, debug_line_offset, td3 );
+         if (has_stmt_list && unit_has_addrs
+            && *debug_line_offset != cu_line_offset) {
+            reset_fndn_ix_table ( fndn_ix_Table, debug_line_offset,
+                                  cu_line_offset );
+            read_filename_table( *fndn_ix_Table, compdir,
+                                 cc, cu_line_offset, td3 );
+         }
       }
    }
 
@@ -3200,9 +3230,9 @@ static Bool parse_inl_DIE (
          if (attr == DW_AT_call_file && cts.szB > 0) {
             Int ftabIx = (Int)cts.u.val;
             if (ftabIx >= 1
-                && ftabIx < VG_(sizeXA)( parser->fndn_ix_Table )) {
+                && ftabIx < VG_(sizeXA)( *fndn_ix_Table )) {
                caller_fndn_ix = *(UInt*)
-                          VG_(indexXA)( parser->fndn_ix_Table, ftabIx );
+                          VG_(indexXA)( *fndn_ix_Table, ftabIx );
             }
             if (0) VG_(printf)("XXX caller_fndn_ix = %u %s\n", caller_fndn_ix,
                                ML_(fndn_ix2filename) (cc->di, caller_fndn_ix));
@@ -4652,6 +4682,8 @@ static void read_DIE (
    /*MOD*/D3TypeParser* typarser,
    /*MOD*/D3VarParser* varparser,
    /*MOD*/D3InlParser* inlparser,
+   XArray** fndn_ix_Table,
+   ULong *debug_line_offset,
    Cursor* c, Bool td3, CUConst* cc, Int level
 )
 {
@@ -4713,6 +4745,8 @@ static void read_DIE (
                      tempvars,
                      gexprs,
                      varparser,
+                     fndn_ix_Table,
+                     debug_line_offset,
                      (DW_TAG)atag,
                      posn,
                      level,
@@ -4734,6 +4768,8 @@ static void read_DIE (
       inlparser->sibling = 0;
       parse_children = 
          parse_inl_DIE( inlparser,
+                        fndn_ix_Table,
+                        debug_line_offset,
                         (DW_TAG)atag,
                         posn,
                         level,
@@ -4773,6 +4809,7 @@ static void read_DIE (
             if (parse_children) {
                read_DIE( rangestree, tyents, tempvars, gexprs,
                          typarser, varparser, inlparser,
+                         fndn_ix_Table, debug_line_offset,
                          c, td3, cc, level+1 );
             } else {
                Int skip_level = level + 1;
@@ -5006,6 +5043,8 @@ void new_dwarf3_reader_wrk (
    D3TypeParser typarser;
    D3VarParser varparser;
    D3InlParser inlparser;
+   XArray* /* of UInt */ fndn_ix_Table = NULL;
+   ULong debug_line_offset = (ULong) -1;
    Word  i, j, n;
    Bool td3 = di->trace_symtab;
    XArray* /* of TempVar* */ dioff_lookup_tab;
@@ -5145,6 +5184,10 @@ void new_dwarf3_reader_wrk (
                       "Overrun whilst reading alternate .debug_info section" );
          section_size = escn_debug_info_alt.szB;
 
+        /* Keep track of the last line table we have seen,
+            it might turn up again.  */
+         reset_fndn_ix_table(&fndn_ix_Table, &debug_line_offset, (ULong) -1);
+
          TRACE_D3("\n------ Parsing alternate .debug_info section ------\n");
       } else if (pass == 1) {
          /* Now loop over the Compilation Units listed in the .debug_info
@@ -5155,6 +5198,10 @@ void new_dwarf3_reader_wrk (
                       "Overrun whilst reading .debug_info section" );
          section_size = escn_debug_info.szB;
 
+        /* Keep track of the last line table we have seen,
+            it might turn up again.  */
+         reset_fndn_ix_table(&fndn_ix_Table, &debug_line_offset, (ULong) -1);
+
          TRACE_D3("\n------ Parsing .debug_info section ------\n");
       } else {
          if (!ML_(sli_is_valid)(escn_debug_types))
@@ -5165,6 +5212,10 @@ void new_dwarf3_reader_wrk (
                       "Overrun whilst reading .debug_types section" );
          section_size = escn_debug_types.szB;
 
+        /* Keep track of the last line table we have seen,
+            it might turn up again.  */
+         reset_fndn_ix_table(&fndn_ix_Table, &debug_line_offset, (ULong) -1);
+
          TRACE_D3("\n------ Parsing .debug_types section ------\n");
       }
 
@@ -5257,26 +5308,6 @@ void new_dwarf3_reader_wrk (
                            unitary_range_list(0UL, ~0UL),
                            -1, False/*isFunc*/, NULL/*fbGX*/ );
 
-            /* And set up the fndn_ix_Table.  When we come across the top
-               level DIE for this CU (which is what the next call to
-               read_DIE should process) we will copy all the file names out
-               of the .debug_line img area and use this table to look up the
-               copies when we later see filename numbers in DW_TAG_variables
-               etc. */
-            vg_assert(!varparser.fndn_ix_Table );
-            varparser.fndn_ix_Table 
-               = VG_(newXA)( ML_(dinfo_zalloc), "di.readdwarf3.ndrw.5var",
-                             ML_(dinfo_free),
-                             sizeof(UInt) );
-         }
-
-         if (VG_(clo_read_inline_info)) {
-            /* fndn_ix_Table for the inlined call parser */
-            vg_assert(!inlparser.fndn_ix_Table );
-            inlparser.fndn_ix_Table 
-               = VG_(newXA)( ML_(dinfo_zalloc), "di.readdwarf3.ndrw.5inl",
-                             ML_(dinfo_free),
-                             sizeof(UInt) );
          }
 
          /* Now read the one-and-only top-level DIE for this CU. */
@@ -5284,6 +5315,7 @@ void new_dwarf3_reader_wrk (
          read_DIE( rangestree,
                    tyents, tempvars, gexprs,
                    &typarser, &varparser, &inlparser,
+                   &fndn_ix_Table, &debug_line_offset,
                    &info, td3, &cc, 0 );
 
          cu_offset_now = get_position_of_Cursor( &info );
@@ -5328,16 +5360,6 @@ void new_dwarf3_reader_wrk (
             typestack_preen( &typarser, td3, -2 );
          }
 
-         if (VG_(clo_read_var_info)) {
-            vg_assert(varparser.fndn_ix_Table );
-            VG_(deleteXA)( varparser.fndn_ix_Table );
-            varparser.fndn_ix_Table = NULL;
-         }
-         if (VG_(clo_read_inline_info)) {
-            vg_assert(inlparser.fndn_ix_Table );
-            VG_(deleteXA)( inlparser.fndn_ix_Table );
-            inlparser.fndn_ix_Table = NULL;
-         }
          clear_CUConst(&cc);
 
          if (cu_offset_now == section_size)
@@ -5346,6 +5368,8 @@ void new_dwarf3_reader_wrk (
       }
    }
 
+   if (fndn_ix_Table != NULL)
+      VG_(deleteXA)(fndn_ix_Table);
 
    if (VG_(clo_read_var_info)) {
       /* From here on we're post-processing the stuff we got
@@ -5662,8 +5686,6 @@ void new_dwarf3_reader_wrk (
       ML_(dinfo_free)( tyents_to_keep_cache );
       tyents_to_keep_cache = NULL;
 
-      vg_assert( varparser.fndn_ix_Table == NULL );
-
       /* And the signatured type hash.  */
       VG_(HT_destruct) ( signature_types, ML_(dinfo_free) );