Optimizing: Rename `As##type` to `As##type##OrNull`.

The null type check in the current implementation of
`HInstruction::As##type()` often cannot be optimized away
by clang++. It is therefore beneficial to have two functions
    HInstruction::As##type()
    HInstruction::As##type##OrNull()
where the first function never returns null but the second
one can return null. The additional text "OrNull" shall also
flag the possibility of yielding null to the developer which
may help avoid bugs similar to what we have seen previously.

This requires renaming the existing function that can return
null and introducing new function that cannot. However,
defining the new function `HInstruction::As##type()` in the
same change as renaming the old one would risk introducing
bugs by missing a rename. Therefore we simply rename the old
function here and the new function shall be introduced in a
separate change with all behavioral changes being explicit.

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Test: buildbot-build.sh --target
Bug: 181943478
Change-Id: I4defd85038e28fe3506903ba3f33f723682b3298

1 files changed, 12 insertions, 7 deletions

diff --git a/compiler/optimizing/induction_var_range.cc b/compiler/optimizing/induction_var_range.cc
index 9b78699ead..107a2c38da 100644
--- a/compiler/optimizing/induction_var_range.cc
+++ b/compiler/optimizing/induction_var_range.cc
@@ -171,8 +171,9 @@ bool UseFullTripCount(const HBasicBlock* context, const HLoopInformation* loop,
   // one edge leaving the loop. The loop header is the only block that's both inside
   // the loop and not in the loop body.
   DCHECK(GetLoopControl(loop)->IsIf());
-  DCHECK_NE(loop->Contains(*GetLoopControl(loop)->AsIf()->IfTrueSuccessor()),
-            loop->Contains(*GetLoopControl(loop)->AsIf()->IfFalseSuccessor()));
+  // TODO: Remove "OrNull".
+  DCHECK_NE(loop->Contains(*GetLoopControl(loop)->AsIfOrNull()->IfTrueSuccessor()),
+            loop->Contains(*GetLoopControl(loop)->AsIfOrNull()->IfFalseSuccessor()));
   if (loop->Contains(*context)) {
     // Use the full trip count if determining the maximum and context is not in the loop body.
     DCHECK_NE(context == loop->GetHeader(), IsContextInBody(context, loop));
@@ -182,8 +183,10 @@ bool UseFullTripCount(const HBasicBlock* context, const HLoopInformation* loop,
     // as long as the `context` is dominated by the loop control exit block.
     // If there are additional exit edges, the value is unknown on those paths.
     HInstruction* loop_control = GetLoopControl(loop);
-    HBasicBlock* then_block = loop_control->AsIf()->IfTrueSuccessor();
-    HBasicBlock* else_block = loop_control->AsIf()->IfFalseSuccessor();
+    // TODO: Remove "OrNull".
+    HBasicBlock* then_block = loop_control->AsIfOrNull()->IfTrueSuccessor();
+    // TODO: Remove "OrNull".
+    HBasicBlock* else_block = loop_control->AsIfOrNull()->IfFalseSuccessor();
     HBasicBlock* loop_exit_block = loop->Contains(*then_block) ? else_block : then_block;
     return loop_exit_block->Dominates(context);
   }
@@ -735,13 +738,15 @@ InductionVarRange::Value InductionVarRange::GetFetch(const HBasicBlock* context,
       return is_min ? Value(0) : Value(std::numeric_limits<int32_t>::max());
     } else if (instruction->InputAt(0)->IsNewArray()) {
       return GetFetch(
-          context, loop, instruction->InputAt(0)->AsNewArray()->GetLength(), trip, is_min);
+          // TODO: Remove "OrNull".
+          context, loop, instruction->InputAt(0)->AsNewArrayOrNull()->GetLength(), trip, is_min);
     }
   } else if (instruction->IsTypeConversion()) {
     // Since analysis is 32-bit (or narrower), chase beyond widening along the path.
     // For example, this discovers the length in: for (long i = 0; i < a.length; i++);
-    if (instruction->AsTypeConversion()->GetInputType() == DataType::Type::kInt32 &&
-        instruction->AsTypeConversion()->GetResultType() == DataType::Type::kInt64) {
+    // TODO: Remove "OrNull".
+    if (instruction->AsTypeConversionOrNull()->GetInputType() == DataType::Type::kInt32 &&
+        instruction->AsTypeConversionOrNull()->GetResultType() == DataType::Type::kInt64) {
       return GetFetch(context, loop, instruction->InputAt(0), trip, is_min);
     }
   }