diff --git a/pkg/compiler/lib/src/ssa/validate.dart b/pkg/compiler/lib/src/ssa/validate.dart
index 99a8f5a9a66..f53f94f019d 100644
--- a/pkg/compiler/lib/src/ssa/validate.dart
+++ b/pkg/compiler/lib/src/ssa/validate.dart
@@ -133,9 +133,17 @@ class HValidator extends HInstructionVisitor {
     super.visitBasicBlock(block);
   }
 
+  // Limit for the size of `inputs` and `usedBy` lists. We assume lists longer
+  // than this are OK in order to avoid the O(N^2) validation getting out of
+  // hand.
+  //
+  // Poster child: corelib_2/regexp/pcre_test.dart, which has a 7KLOC main().
+  static const int kMaxValidatedInstructionListLength = 1000;
+
   /// Verifies [instruction] is contained in [instructions] [count] times.
   static bool checkInstructionCount(
       List<HInstruction> instructions, HInstruction instruction, int count) {
+    if (instructions.length > kMaxValidatedInstructionListLength) return true;
     int result = 0;
     for (int i = 0; i < instructions.length; i++) {
       if (identical(instructions[i], instruction)) result++;
@@ -146,7 +154,9 @@ class HValidator extends HInstructionVisitor {
   /// Returns true if the predicate returns true for every instruction in the
   /// list. The argument to [f] is an instruction with the count of how often
   /// it appeared in the list [instructions].
-  static bool everyInstruction(List<HInstruction> instructions, Function f) {
+  static bool everyInstruction(
+      List<HInstruction> instructions, bool Function(HInstruction, int) f) {
+    if (instructions.length > kMaxValidatedInstructionListLength) return true;
     var copy = new List<HInstruction>.from(instructions);
     // TODO(floitsch): there is currently no way to sort HInstructions before
     // we have assigned an ID. The loop is therefore O(n^2) for now.
diff --git a/tests/compiler/dart2js/analyses/dart2js_allowed.json b/tests/compiler/dart2js/analyses/dart2js_allowed.json
index 0b70e2e52c8..ff6c98ad732 100644
--- a/tests/compiler/dart2js/analyses/dart2js_allowed.json
+++ b/tests/compiler/dart2js/analyses/dart2js_allowed.json
@@ -146,6 +146,15 @@
     "Dynamic invocation of '-'.": 1,
     "Dynamic invocation of '+'.": 1
   },
+  "pkg/compiler/lib/src/serialization/binary_sink.dart": {
+    "Dynamic access of 'index'.": 1
+  },
+  "pkg/compiler/lib/src/native/behavior.dart": {
+    "Dynamic invocation of 'add'.": 1
+  },
+  "pkg/compiler/lib/src/util/enumset.dart": {
+    "Dynamic access of 'index'.": 4
+  },
   "pkg/compiler/lib/src/constants/constant_system.dart": {
     "Dynamic invocation of '&'.": 1,
     "Dynamic invocation of '|'.": 1,
@@ -165,9 +174,6 @@
     "Dynamic invocation of '>='.": 1,
     "Dynamic invocation of 'codeUnitAt'.": 1
   },
-  "pkg/compiler/lib/src/serialization/binary_sink.dart": {
-    "Dynamic access of 'index'.": 1
-  },
   "third_party/pkg/dart2js_info/lib/json_info_codec.dart": {
     "Dynamic invocation of '[]'.": 11,
     "Dynamic invocation of 'forEach'.": 2,
@@ -177,12 +183,6 @@
   "third_party/pkg/dart2js_info/lib/binary_serialization.dart": {
     "Dynamic invocation of 'cast'.": 1
   },
-  "pkg/compiler/lib/src/util/enumset.dart": {
-    "Dynamic access of 'index'.": 4
-  },
-  "pkg/compiler/lib/src/native/enqueue.dart": {
-    "Dynamic access of 'isDynamic'.": 1
-  },
   "pkg/compiler/lib/src/inferrer/inferrer_engine.dart": {
     "Dynamic access of 'isVoid'.": 1,
     "Dynamic access of 'isDynamic'.": 1,
@@ -195,8 +195,8 @@
   "pkg/compiler/lib/src/universe/side_effects.dart": {
     "Dynamic access of 'universe.side_effects::_flags'.": 1
   },
-  "pkg/compiler/lib/src/native/behavior.dart": {
-    "Dynamic invocation of 'add'.": 1
+  "pkg/compiler/lib/src/native/enqueue.dart": {
+    "Dynamic access of 'isDynamic'.": 1
   },
   "pkg/compiler/lib/src/ssa/builder_kernel.dart": {
     "Dynamic update to 'instantiatedTypes'.": 1,
@@ -211,17 +211,11 @@
     "Dynamic access of 'treatAsDynamic'.": 1,
     "Dynamic access of 'element'.": 1
   },
-  "pkg/compiler/lib/src/ssa/validate.dart": {
-    "Dynamic invocation of 'isInBasicBlock'.": 2,
-    "Dynamic access of 'usedBy'.": 2,
-    "Dynamic access of 'inputs'.": 1
-  },
-  "third_party/pkg/dart2js_info/lib/src/util.dart": {
-    "Dynamic access of 'name'.": 1,
-    "Dynamic invocation of '-'.": 1
-  },
-  "third_party/pkg/dart2js_info/lib/src/binary/sink.dart": {
-    "Dynamic access of 'index'.": 1
+  "pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart": {
+    "Dynamic access of 'keys'.": 1,
+    "Dynamic invocation of 'toSet'.": 1,
+    "Dynamic invocation of '[]='.": 1,
+    "Dynamic invocation of 'add'.": 1
   },
   "pkg/js_ast/lib/src/builder.dart": {
     "Dynamic invocation of 'call'.": 2
@@ -235,6 +229,13 @@
     "Dynamic invocation of '[]'.": 9,
     "Dynamic invocation of 'toStatement'.": 3
   },
+  "third_party/pkg/dart2js_info/lib/src/util.dart": {
+    "Dynamic access of 'name'.": 1,
+    "Dynamic invocation of '-'.": 1
+  },
+  "third_party/pkg/dart2js_info/lib/src/binary/sink.dart": {
+    "Dynamic access of 'index'.": 1
+  },
   "pkg/compiler/lib/src/inferrer/type_graph_nodes.dart": {
     "Dynamic invocation of 'add'.": 1,
     "Dynamic invocation of 'remove'.": 1,
@@ -250,16 +251,14 @@
     "Dynamic access of 'named'.": 2,
     "Dynamic invocation of '[]'.": 2
   },
-  "pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart": {
-    "Dynamic access of 'keys'.": 1,
-    "Dynamic invocation of 'toSet'.": 1,
-    "Dynamic invocation of '[]='.": 1,
-    "Dynamic invocation of 'add'.": 1
-  },
   "pkg/compiler/lib/src/universe/function_set.dart": {
     "Dynamic access of 'selector'.": 1,
     "Dynamic access of 'receiver'.": 1
   },
+  "pkg/compiler/lib/src/js_emitter/startup_emitter/fragment_emitter.dart": {
+    "Dynamic access of 'superclass'.": 1,
+    "Dynamic access of 'needsTearOff'.": 1
+  },
   "pkg/compiler/lib/src/ssa/variable_allocator.dart": {
     "Dynamic access of 'usedBy'.": 1,
     "Dynamic access of 'isEmpty'.": 1,
@@ -275,9 +274,5 @@
   },
   "pkg/compiler/lib/src/ssa/value_set.dart": {
     "Dynamic invocation of 'add'.": 2
-  },
-  "pkg/compiler/lib/src/js_emitter/startup_emitter/fragment_emitter.dart": {
-    "Dynamic access of 'superclass'.": 1,
-    "Dynamic access of 'needsTearOff'.": 1
   }
 }
\ No newline at end of file