[turbofan] Fix GVN of projections and add verification for projection uniqueness.

src/compiler/common-operator.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/compiler/common-operator.h"
 
 #include "src/assembler.h"
 #include "src/base/lazy-instance.h"
 #include "src/compiler/linkage.h"
 #include "src/compiler/opcodes.h"
@@ skipping 274 matching lines @@
               kIndex) {}                              // parameter
   };
 #define CACHED_PARAMETER(index) \
   ParameterOperator<index> kParameter##index##Operator;
   CACHED_PARAMETER_LIST(CACHED_PARAMETER)
 #undef CACHED_PARAMETER
 
   template <size_t kIndex>
   struct ProjectionOperator FINAL : public Operator1<size_t> {
     ProjectionOperator()
-        : Operator1<size_t>(                             // --
-              IrOpcode::kProjection,                     // opcode
-              Operator::kFoldable | Operator::kNoThrow,  // flags
-              "Projection",                              // name
-              1, 0, 0, 1, 0, 0,                          // counts,
-              kIndex) {}                                 // parameter
+        : Operator1<size_t>(          // --
+              IrOpcode::kProjection,  // opcode
+              Operator::kPure,        // flags
+              "Projection",           // name
+              1, 0, 0, 1, 0, 0,       // counts,
+              kIndex) {}              // parameter
   };
 #define CACHED_PROJECTION(index) \
   ProjectionOperator<index> kProjection##index##Operator;
   CACHED_PROJECTION_LIST(CACHED_PROJECTION)
 #undef CACHED_PROJECTION
 
   template <int kInputCount>
   struct StateValuesOperator FINAL : public Operator {
     StateValuesOperator()
         : Operator(                           // --
@@ skipping 358 matching lines @@
   } else {
     UNREACHABLE();
     return nullptr;
   }
 }
 
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8