[test] make instruction sequence test emit cfgs more like the scheduler

BUG=

Review URL: https://codereview.chromium.org/1116923002

Cr-Commit-Position: refs/heads/master@{#28167}

test/unittests/compiler/instruction-sequence-unittest.cc

@@ -109,7 +109,7 @@ Instruction* InstructionSequenceTest::EndBlock(BlockCompletion completion) {
     case kBlockEnd:
       break;
     case kFallThrough:
-      result = EmitFallThrough();
+      result = EmitJump();
       break;
     case kJump:
       CHECK(!block_returns_);
@@ -441,11 +441,20 @@ InstructionBlock* InstructionSequenceTest::NewBlock() {
 void InstructionSequenceTest::WireBlocks() {
   CHECK(!current_block());
   CHECK(instruction_blocks_.size() == completions_.size());
+  CHECK(loop_blocks_.empty());
+  // Wire in end block to look like a scheduler produced cfg.
+  auto end_block = NewBlock();
+  current_block_ = nullptr;
+  sequence()->EndBlock(end_block->rpo_number());
   size_t offset = 0;
   for (const auto& completion : completions_) {
     switch (completion.type_) {
-      case kBlockEnd:
+      case kBlockEnd: {
+        auto block = instruction_blocks_[offset];
+        block->successors().push_back(end_block->rpo_number());
+        end_block->predecessors().push_back(block->rpo_number());
         break;
+      }
       case kFallThrough:  // Fallthrough.
       case kJump:
         WireBlock(offset, completion.offset_0_);

test/unittests/compiler/move-optimizer-unittest.cc

@@ -136,9 +136,11 @@ TEST_F(MoveOptimizerTest, SimpleMerge) {
   StartBlock();
   EndBlock(Last());
 
+  auto last = LastInstruction();
+
   Optimize();
 
-  auto move = LastInstruction()->parallel_moves()[0];
+  auto move = last->parallel_moves()[0];
   CHECK_EQ(1, NonRedundantSize(move));
   CHECK(Contains(move, Reg(0), Reg(1)));
 }
@@ -163,11 +165,13 @@ TEST_F(MoveOptimizerTest, SimpleMergeCycle) {
   StartBlock();
   EndBlock(Last());
 
+  auto last = LastInstruction();
+
   Optimize();
 
   CHECK(gap_0->AreMovesRedundant());
   CHECK(gap_1->AreMovesRedundant());
-  auto move = LastInstruction()->parallel_moves()[0];
+  auto move = last->parallel_moves()[0];
   CHECK_EQ(2, NonRedundantSize(move));
   CHECK(Contains(move, Reg(0), Reg(1)));
   CHECK(Contains(move, Reg(1), Reg(0)));