1 files changed, 147 insertions, 0 deletions
diff --git a/js/src/jsapi-tests/testJitDCEinGVN.cpp b/js/src/jsapi-tests/testJitDCEinGVN.cpp
new file mode 100644
index 0000000000..286d36aa14
--- /dev/null
+++ b/js/src/jsapi-tests/testJitDCEinGVN.cpp
@@ -0,0 +1,147 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "jit/IonAnalysis.h"
+#include "jit/MIRGenerator.h"
+#include "jit/MIRGraph.h"
+#include "jit/ValueNumbering.h"
+
+#include "jsapi-tests/testJitMinimalFunc.h"
+#include "jsapi-tests/tests.h"
+
+using namespace js;
+using namespace js::jit;
+
+BEGIN_TEST(testJitDCEinGVN_ins) {
+  MinimalFunc func;
+  MBasicBlock* block = func.createEntryBlock();
+
+  // mul0 = p * p
+  // mul1 = mul0 * mul0
+  // return p
+  MParameter* p = func.createParameter();
+  block->add(p);
+  MMul* mul0 = MMul::New(func.alloc, p, p, MIRType::Double);
+  block->add(mul0);
+  if (!mul0->typePolicy()->adjustInputs(func.alloc, mul0)) {
+    return false;
+  }
+  MMul* mul1 = MMul::New(func.alloc, mul0, mul0, MIRType::Double);
+  block->add(mul1);
+  if (!mul1->typePolicy()->adjustInputs(func.alloc, mul1)) {
+    return false;
+  }
+  MReturn* ret = MReturn::New(func.alloc, p);
+  block->end(ret);
+
+  if (!func.runGVN()) {
+    return false;
+  }
+
+  // mul0 and mul1 should be deleted.
+  for (MInstructionIterator ins = block->begin(); ins != block->end(); ins++) {
+    CHECK(!ins->isMul() ||
+          (ins->getOperand(0) != p && ins->getOperand(1) != p));
+    CHECK(!ins->isMul() ||
+          (ins->getOperand(0) != mul0 && ins->getOperand(1) != mul0));
+  }
+  return true;
+}
+END_TEST(testJitDCEinGVN_ins)
+
+BEGIN_TEST(testJitDCEinGVN_phi) {
+  MinimalFunc func;
+  MBasicBlock* block = func.createEntryBlock();
+  MBasicBlock* thenBlock1 = func.createBlock(block);
+  MBasicBlock* thenBlock2 = func.createBlock(block);
+  MBasicBlock* elifBlock = func.createBlock(block);
+  MBasicBlock* elseBlock = func.createBlock(block);
+  MBasicBlock* joinBlock = func.createBlock(block);
+
+  // if (p) {
+  //   x = 1.0;
+  //   y = 3.0;
+  // } else if (q) {
+  //   x = 2.0;
+  //   y = 4.0;
+  // } else {
+  //   x = 1.0;
+  //   y = 5.0;
+  // }
+  // x = phi(1.0, 2.0, 1.0);
+  // y = phi(3.0, 4.0, 5.0);
+  // z = x * y;
+  // return y;
+
+  MConstant* c1 = MConstant::New(func.alloc, DoubleValue(1.0));
+  block->add(c1);
+  MPhi* x = MPhi::New(func.alloc);
+  MPhi* y = MPhi::New(func.alloc);
+
+  // if (p) {
+  MParameter* p = func.createParameter();
+  block->add(p);
+  block->end(MTest::New(func.alloc, p, thenBlock1, elifBlock));
+
+  //   x = 1.0
+  //   y = 3.0;
+  MOZ_RELEASE_ASSERT(x->addInputSlow(c1));
+  MConstant* c3 = MConstant::New(func.alloc, DoubleValue(3.0));
+  thenBlock1->add(c3);
+  MOZ_RELEASE_ASSERT(y->addInputSlow(c3));
+  thenBlock1->end(MGoto::New(func.alloc, joinBlock));
+  MOZ_ALWAYS_TRUE(joinBlock->addPredecessor(func.alloc, thenBlock1));
+
+  // } else if (q) {
+  MParameter* q = func.createParameter();
+  elifBlock->add(q);
+  elifBlock->end(MTest::New(func.alloc, q, thenBlock2, elseBlock));
+
+  //   x = 2.0
+  //   y = 4.0;
+  MConstant* c2 = MConstant::New(func.alloc, DoubleValue(2.0));
+  thenBlock2->add(c2);
+  MOZ_RELEASE_ASSERT(x->addInputSlow(c2));
+  MConstant* c4 = MConstant::New(func.alloc, DoubleValue(4.0));
+  thenBlock2->add(c4);
+  MOZ_RELEASE_ASSERT(y->addInputSlow(c4));
+  thenBlock2->end(MGoto::New(func.alloc, joinBlock));
+  MOZ_ALWAYS_TRUE(joinBlock->addPredecessor(func.alloc, thenBlock2));
+
+  // } else {
+  //   x = 1.0
+  //   y = 5.0;
+  // }
+  MOZ_RELEASE_ASSERT(x->addInputSlow(c1));
+  MConstant* c5 = MConstant::New(func.alloc, DoubleValue(5.0));
+  elseBlock->add(c5);
+  MOZ_RELEASE_ASSERT(y->addInputSlow(c5));
+  elseBlock->end(MGoto::New(func.alloc, joinBlock));
+  MOZ_ALWAYS_TRUE(joinBlock->addPredecessor(func.alloc, elseBlock));
+
+  // x = phi(1.0, 2.0, 1.0)
+  // y = phi(3.0, 4.0, 5.0)
+  // z = x * y
+  // return y
+  joinBlock->addPhi(x);
+  joinBlock->addPhi(y);
+  MMul* z = MMul::New(func.alloc, x, y, MIRType::Double);
+  joinBlock->add(z);
+  MReturn* ret = MReturn::New(func.alloc, y);
+  joinBlock->end(ret);
+
+  if (!func.runGVN()) {
+    return false;
+  }
+
+  // c1 should be deleted.
+  for (MInstructionIterator ins = block->begin(); ins != block->end(); ins++) {
+    CHECK(!ins->isConstant() || (ins->toConstant()->numberToDouble() != 1.0));
+  }
+  return true;
+}
+END_TEST(testJitDCEinGVN_phi)