Added ability to generate last-value of linear induction.

Also added utility to update fetches in induction nodes.

Rationale:
This is a first step towards the larger CL that introduces
a new loop optimization framework in the optimizing compiler
(see https://android-review.googlesource.com/#/c/271392/3).

Change-Id: Ibecd674c8146d9665340e68718c498555646129a
Tests: induction_var_range_test

1 files changed, 5 insertions, 8 deletions

diff --git a/compiler/optimizing/bounds_check_elimination.cc b/compiler/optimizing/bounds_check_elimination.cc
index 8aefd9ea1f..994d394a2a 100644
--- a/compiler/optimizing/bounds_check_elimination.cc
+++ b/compiler/optimizing/bounds_check_elimination.cc
@@ -887,7 +887,7 @@ class BCEVisitor : public HGraphVisitor {
       bool needs_finite_test = false;
       bool needs_taken_test = false;
       if (DynamicBCESeemsProfitable(loop, bounds_check->GetBlock()) &&
-          induction_range_.CanGenerateCode(
+          induction_range_.CanGenerateRange(
               bounds_check, index, &needs_finite_test, &needs_taken_test) &&
           CanHandleInfiniteLoop(loop, index, needs_finite_test) &&
           // Do this test last, since it may generate code.
@@ -1403,10 +1403,10 @@ class BCEVisitor : public HGraphVisitor {
           // whether code generation on the original and, thus, related bounds check was possible.
           // It handles either loop invariants (lower is not set) or unit strides.
           if (other_c == max_c) {
-            induction_range_.GenerateRangeCode(
+            induction_range_.GenerateRange(
                 other_bounds_check, other_index, GetGraph(), block, &max_lower, &max_upper);
           } else if (other_c == min_c && base != nullptr) {
-            induction_range_.GenerateRangeCode(
+            induction_range_.GenerateRange(
                 other_bounds_check, other_index, GetGraph(), block, &min_lower, &min_upper);
           }
           ReplaceInstruction(other_bounds_check, other_index);
@@ -1699,11 +1699,8 @@ class BCEVisitor : public HGraphVisitor {
     // Insert the taken-test to see if the loop body is entered. If the
     // loop isn't entered at all, it jumps around the deoptimization block.
     if_block->AddInstruction(new (GetGraph()->GetArena()) HGoto());  // placeholder
-    HInstruction* condition = nullptr;
-    induction_range_.GenerateTakenTest(header->GetLastInstruction(),
-                                       GetGraph(),
-                                       if_block,
-                                       &condition);
+    HInstruction* condition = induction_range_.GenerateTakenTest(
+        header->GetLastInstruction(), GetGraph(), if_block);
     DCHECK(condition != nullptr);
     if_block->RemoveInstruction(if_block->GetLastInstruction());
     if_block->AddInstruction(new (GetGraph()->GetArena()) HIf(condition));