From 24b069cd53cec2d8afa4e7b90cf5b47c91e215c9 Mon Sep 17 00:00:00 2001
From: Behdad Esfahbod <behdad@behdad.org>
Date: Fri, 2 Jun 2023 15:55:53 -0600
Subject: [PATCH] [subset] Pre-alloc a few maps

---
 src/hb-multimap.hh               |  5 +++++
 src/hb-ot-post-table-v2subset.hh | 12 +++++++++---
 src/hb-subset-plan.cc            |  2 ++
 3 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/src/hb-multimap.hh b/src/hb-multimap.hh
index b4a8cc62a..42d6c8aae 100644
--- a/src/hb-multimap.hh
+++ b/src/hb-multimap.hh
@@ -81,6 +81,11 @@ struct hb_multimap_t
     return singulars.in_error () || multiples_indices.in_error () || multiples_values.in_error ();
   }
 
+  void resize (unsigned size)
+  {
+    singulars.resize (size);
+  }
+
   protected:
   hb_map_t singulars;
   hb_map_t multiples_indices;
diff --git a/src/hb-ot-post-table-v2subset.hh b/src/hb-ot-post-table-v2subset.hh
index 951e6395d..c184ad1a5 100644
--- a/src/hb-ot-post-table-v2subset.hh
+++ b/src/hb-ot-post-table-v2subset.hh
@@ -79,6 +79,11 @@ HB_INTERNAL bool postV2Tail::subset (hb_subset_context_t *c) const
   post::accelerator_t _post (c->plan->source);
 
   hb_hashmap_t<hb_bytes_t, uint32_t, true> glyph_name_to_new_index;
+
+  old_new_index_map.resize (num_glyphs);
+  old_gid_new_index_map.resize (num_glyphs);
+  glyph_name_to_new_index.resize (num_glyphs);
+
   for (hb_codepoint_t new_gid = 0; new_gid < num_glyphs; new_gid++)
   {
     hb_codepoint_t old_gid = reverse_glyph_map.get (new_gid);
@@ -86,11 +91,12 @@ HB_INTERNAL bool postV2Tail::subset (hb_subset_context_t *c) const
 
     unsigned new_index;
     const uint32_t *new_index2;
-    if (old_index <= 257) new_index = old_index;
+    if (old_index <= 257)
+      new_index = old_index;
     else if (old_new_index_map.has (old_index, &new_index2))
-    {
       new_index = *new_index2;
-    } else {
+    else
+    {
       hb_bytes_t s = _post.find_glyph_name (old_gid);
       new_index = glyph_name_to_new_index.get (s);
       if (new_index == (unsigned)-1)
diff --git a/src/hb-subset-plan.cc b/src/hb-subset-plan.cc
index 506aba0fc..38ef76da5 100644
--- a/src/hb-subset-plan.cc
+++ b/src/hb-subset-plan.cc
@@ -769,6 +769,7 @@ _create_glyph_map_gsub (const hb_set_t* glyph_set_gsub,
                         const hb_map_t* glyph_map,
                         hb_map_t* out)
 {
+  out->resize (glyph_set_gsub->get_population ());
   + hb_iter (glyph_set_gsub)
   | hb_map ([&] (hb_codepoint_t gid) {
     return hb_pair_t<hb_codepoint_t, hb_codepoint_t> (gid,
@@ -1130,6 +1131,7 @@ hb_subset_plan_t::hb_subset_plan_t (hb_face_t *face,
 
     hb_map_t &unicode_to_gid = *codepoint_to_glyph;
 
+    gid_to_unicodes.resize (unicodes.get_population ());
     for (auto unicode : unicodes)
     {
       auto gid = unicode_to_gid[unicode];