xkbcomp/scanner: avoid unneeded strdup of IDENT tokens

The allocation is immediately discarded, either turned into a keysym or an atom. So use an sval slice into the input string instead strdup'ing. memusage ./release/bench-compile-keymap --iter=1000 --layout us,de --variant ,neo Before: Memory usage summary: heap total: 534063576, heap peak: 581022, stack peak: 18848 total calls total memory failed calls malloc| 11240525 291897104 0 realloc| 1447657 192307328 0 (nomove:37629, dec:0, free:0) calloc| 430573 49859144 0 free| 13993903 534063576 After: Memory usage summary: heap total: 506839909, heap peak: 581022, stack peak: 18960 total calls total memory failed calls malloc| 8016419 264673437 0 realloc| 1447657 192307328 0 (nomove:37278, dec:0, free:0) calloc| 430573 49859144 0 free| 0769797 506839909 Signed-off-by: Ran Benita <[email protected]>
xkbcommon · Feb 3, 2025 · 584b1a1 · 584b1a1
1 parent e953159
commit 584b1a1
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Showing 5 changed files with 29 additions and 17 deletions.
diff --git a/src/scanner-utils.h b/src/scanner-utils.h
@@ -48,12 +48,21 @@ svaleq(struct sval s1, struct sval s2)
     return s1.len == s2.len && memcmp(s1.start, s2.start, s1.len) == 0;
 }
 
+static inline bool
+isvaleq(struct sval s1, struct sval s2)
+{
+    return s1.len == s2.len && istrncmp(s1.start, s2.start, s1.len) == 0;
+}
+
 static inline bool
 svaleq_prefix(struct sval s1, struct sval s2)
 {
     return s1.len <= s2.len && memcmp(s1.start, s2.start, s1.len) == 0;
 }
 
+#define SVAL(start, len) (struct sval){(start), len}
+#define SVAL_LIT(literal) SVAL(literal, sizeof(literal) - 1)
+
 /* A line:column location in the input string (1-based). */
 struct scanner_loc {
     size_t line, column;

diff --git a/src/xkbcomp/parser-priv.h b/src/xkbcomp/parser-priv.h
@@ -30,6 +30,7 @@
 struct parser_param;
 struct scanner;
 
+#include "scanner-utils.h"
 #include "parser.h"
 
 int

diff --git a/src/xkbcomp/parser.y b/src/xkbcomp/parser.y
@@ -36,7 +36,6 @@
 #include "xkbcomp/xkbcomp-priv.h"
 #include "xkbcomp/ast-build.h"
 #include "xkbcomp/parser-priv.h"
-#include "scanner-utils.h"
 #include "keysym.h"
 
 struct parser_param {
@@ -59,25 +58,32 @@ _xkbcommon_error(struct parser_param *param, const char *msg)
 }
 
 static bool
-resolve_keysym(struct parser_param *param, const char *name, xkb_keysym_t *sym_rtrn)
+resolve_keysym(struct parser_param *param, struct sval name, xkb_keysym_t *sym_rtrn)
 {
     xkb_keysym_t sym;
 
-    if (!name || istreq(name, "any") || istreq(name, "nosymbol")) {
+    if (isvaleq(name, SVAL_LIT("any")) || isvaleq(name, SVAL_LIT("nosymbol"))) {
         *sym_rtrn = XKB_KEY_NoSymbol;
         return true;
     }
 
-    if (istreq(name, "none") || istreq(name, "voidsymbol")) {
+    if (isvaleq(name, SVAL_LIT("none")) || isvaleq(name, SVAL_LIT("voidsymbol"))) {
         *sym_rtrn = XKB_KEY_VoidSymbol;
         return true;
     }
 
-    sym = xkb_keysym_from_name(name, XKB_KEYSYM_NO_FLAGS);
+    char buf[256];
+    if (name.len >= sizeof(buf)) {
+        return false;
+    }
+    memcpy(buf, name.start, name.len);
+    buf[name.len] = '\0';
+
+    sym = xkb_keysym_from_name(buf, XKB_KEYSYM_NO_FLAGS);
     if (sym != XKB_KEY_NoSymbol) {
         *sym_rtrn = sym;
         check_deprecated_keysyms(parser_warn, param, param->ctx,
-                                 sym, name, name, "%s", "");
+                                 sym, buf, buf, "%s", "");
         return true;
     }
 
@@ -168,6 +174,7 @@ resolve_keysym(struct parser_param *param, const char *name, xkb_keysym_t *sym_r
         int64_t          num;
         enum xkb_file_type file_type;
         char            *str;
+        struct sval     sval;
         xkb_atom_t      atom;
         enum merge_mode merge;
         enum xkb_map_flags mapFlags;
@@ -195,7 +202,8 @@ resolve_keysym(struct parser_param *param, const char *name, xkb_keysym_t *sym_r
 }
 
 %type <num>     INTEGER FLOAT
-%type <str>     IDENT STRING
+%type <str>     STRING
+%type <sval>    IDENT
 %type <atom>    KEYNAME
 %type <num>     KeyCode Number Integer Float SignedNumber DoodadType
 %type <merge>   MergeMode OptMergeMode
@@ -765,12 +773,11 @@ KeySym          :       IDENT
                                 parser_warn(
                                     param,
                                     XKB_WARNING_UNRECOGNIZED_KEYSYM,
-                                    "unrecognized keysym \"%s\"",
-                                    $1
+                                    "unrecognized keysym \"%.*s\"",
+                                    $1.len, $1.start
                                 );
                                 $$ = XKB_KEY_NoSymbol;
                             }
-                            free($1);
                         }
                         /* Handle keysym that is also a keyword  */
                 |       SECTION { $$ = XKB_KEY_section; }
@@ -829,7 +836,7 @@ Integer         :       INTEGER { $$ = $1; }
 KeyCode         :       INTEGER { $$ = $1; }
                 ;
 
-Ident           :       IDENT   { $$ = xkb_atom_intern(param->ctx, $1, strlen($1)); free($1); }
+Ident           :       IDENT   { $$ = xkb_atom_intern(param->ctx, $1.start, $1.len); }
                 |       DEFAULT { $$ = xkb_atom_intern_literal(param->ctx, "default"); }
                 ;
 

diff --git a/src/xkbcomp/rules.c b/src/xkbcomp/rules.c
@@ -172,8 +172,6 @@ enum rules_mlvo {
     _MLVO_NUM_ENTRIES
 };
 
-#define SVAL_LIT(literal) { literal, sizeof(literal) - 1 }
-
 static const struct sval rules_mlvo_svals[_MLVO_NUM_ENTRIES] = {
     [MLVO_MODEL] = SVAL_LIT("model"),
     [MLVO_LAYOUT] = SVAL_LIT("layout"),

diff --git a/src/xkbcomp/scanner.c b/src/xkbcomp/scanner.c
@@ -25,7 +25,6 @@
 
 #include "xkbcomp-priv.h"
 #include "parser-priv.h"
-#include "scanner-utils.h"
 
 static bool
 number(struct scanner *s, int64_t *out, int *out_tok)
@@ -174,9 +173,7 @@ _xkbcommon_lex(YYSTYPE *yylval, struct scanner *s)
         tok = keyword_to_token(start, len);
         if (tok >= 0) return tok;
 
-        yylval->str = strndup(start, len);
-        if (!yylval->str)
-            return ERROR_TOK;
+        yylval->sval = SVAL(start, len);
         return IDENT;
     }