From 968d4d9cdd647b83e5f0c32cfcff80536dfaddc3 Mon Sep 17 00:00:00 2001
From: Max Schaefer <max@semmle.com>
Date: Wed, 29 Apr 2020 14:37:46 +0100
Subject: [PATCH] Revert the join order fix from
 https://github.com/github/codeql/pull/2872.

cf https://github.com/github/codeql/pull/3202
---
 .../go/dataflow/internal/DataFlowImpl.qll     | 27 +++++--------------
 1 file changed, 7 insertions(+), 20 deletions(-)

diff --git a/ql/src/semmle/go/dataflow/internal/DataFlowImpl.qll b/ql/src/semmle/go/dataflow/internal/DataFlowImpl.qll
index 50a5e284dfd..a305dc25a36 100644
--- a/ql/src/semmle/go/dataflow/internal/DataFlowImpl.qll
+++ b/ql/src/semmle/go/dataflow/internal/DataFlowImpl.qll
@@ -2293,12 +2293,13 @@ private class PathNodeSink extends PathNodeImpl, TPathNodeSink {
  * a callable is recorded by `cc`.
  */
 private predicate pathStep(PathNodeMid mid, Node node, CallContext cc, SummaryCtx sc, AccessPath ap) {
-  exists(
-    AccessPath ap0, Node midnode, Configuration conf, DataFlowCallable enclosing,
-    LocalCallContext localCC
-  |
-    pathIntoLocalStep(mid, midnode, cc, enclosing, sc, ap0, conf) and
-    localCC = getLocalCallContext(cc, enclosing)
+  exists(AccessPath ap0, Node midnode, Configuration conf, LocalCallContext localCC |
+    midnode = mid.getNode() and
+    conf = mid.getConfiguration() and
+    cc = mid.getCallContext() and
+    sc = mid.getSummaryCtx() and
+    localCC = getLocalCallContext(cc, midnode.getEnclosingCallable()) and
+    ap0 = mid.getAp()
   |
     localFlowBigStep(midnode, node, true, _, conf, localCC) and
     ap = ap0
@@ -2331,20 +2332,6 @@ private predicate pathStep(PathNodeMid mid, Node node, CallContext cc, SummaryCt
   pathThroughCallable(mid, node, cc, ap) and sc = mid.getSummaryCtx()
 }
 
-pragma[nomagic]
-private predicate pathIntoLocalStep(
-  PathNodeMid mid, Node midnode, CallContext cc, DataFlowCallable enclosing, SummaryCtx sc,
-  AccessPath ap0, Configuration conf
-) {
-  midnode = mid.getNode() and
-  cc = mid.getCallContext() and
-  conf = mid.getConfiguration() and
-  localFlowBigStep(midnode, _, _, _, conf, _) and
-  enclosing = midnode.getEnclosingCallable() and
-  sc = mid.getSummaryCtx() and
-  ap0 = mid.getAp()
-}
-
 pragma[nomagic]
 private predicate readCand(Node node1, Content f, Node node2, Configuration config) {
   readDirect(node1, f, node2) and