From 4e55cd973bbcc08154c6e6d6ccd2ae2d4d4199ff Mon Sep 17 00:00:00 2001
From: Slava Pestov <slava@slava-pestovs-macbook-pro.local>
Date: Thu, 6 Nov 2008 11:48:55 -0600
Subject: [PATCH] If a #dispatch branch is a call to another word which is not
 an intrinsic, we avoid generating the dispatch branch and just jump to the
 word directly

---
 basis/compiler/cfg/builder/builder.factor | 35 +++++++++++++++--------
 1 file changed, 23 insertions(+), 12 deletions(-)

diff --git a/basis/compiler/cfg/builder/builder.factor b/basis/compiler/cfg/builder/builder.factor
index 5b9f2e068b..93daa601fe 100755
--- a/basis/compiler/cfg/builder/builder.factor
+++ b/basis/compiler/cfg/builder/builder.factor
@@ -156,19 +156,30 @@ M: #if emit-node
     } cond iterate-next ;
 
 ! #dispatch
+: trivial-dispatch-branch? ( nodes -- ? )
+    dup length 1 = [
+        first dup #call? [
+            word>> "intrinsic" word-prop not
+        ] [ drop f ] if
+    ] [ drop f ] if ;
+
 : dispatch-branch ( nodes word -- label )
-    gensym [
-        [
-            V{ } clone node-stack set
-            ##prologue
-            emit-nodes
-            basic-block get [
-                ##epilogue
-                ##return
-                end-basic-block
-            ] when
-        ] with-cfg-builder
-    ] keep ;
+    over trivial-dispatch-branch? [
+        drop first word>>
+    ] [
+        gensym [
+            [
+                V{ } clone node-stack set
+                ##prologue
+                emit-nodes
+                basic-block get [
+                    ##epilogue
+                    ##return
+                    end-basic-block
+                ] when
+            ] with-cfg-builder
+        ] keep
+    ] if ;
 
 : dispatch-branches ( node -- )
     children>> [