Merge "Fix bug in vectorization of charAt, with regression test"

2 files changed, 21 insertions, 0 deletions

diff --git a/compiler/optimizing/loop_optimization.cc b/compiler/optimizing/loop_optimization.cc
index 8eeff1f2f0..cf7acb36d1 100644
--- a/compiler/optimizing/loop_optimization.cc
+++ b/compiler/optimizing/loop_optimization.cc
@@ -623,6 +623,12 @@ bool HLoopOptimization::VectorizeUse(LoopNode* node,
     }
     return true;
   } else if (instruction->IsArrayGet()) {
+    // Strings are different, with a different offset to the actual data
+    // and some compressed to save memory. For now, all cases are rejected
+    // to avoid the complexity.
+    if (instruction->AsArrayGet()->IsStringCharAt()) {
+      return false;
+    }
     // Accept a right-hand-side array base[index] for
     // (1) exact matching vector type,
     // (2) loop-invariant base,
diff --git a/test/623-checker-loop-regressions/src/Main.java b/test/623-checker-loop-regressions/src/Main.java
index 182c07d983..f0b327840c 100644
--- a/test/623-checker-loop-regressions/src/Main.java
+++ b/test/623-checker-loop-regressions/src/Main.java
@@ -280,6 +280,14 @@ public class Main {
     }
   }
 
+  // If vectorized, string encoding should be dealt with.
+  private static void string2Bytes(char[] a, String b) {
+    int min = Math.min(a.length, b.length());
+    for (int i = 0; i < min; i++) {
+      a[i] = b.charAt(i);
+    }
+  }
+
   public static void main(String[] args) {
     expectEquals(10, earlyExitFirst(-1));
     for (int i = 0; i <= 10; i++) {
@@ -354,6 +362,13 @@ public class Main {
       expectEquals(2, yy[i]);
     }
 
+    char[] aa = new char[23];
+    String bb = "hello world how are you";
+    string2Bytes(aa, bb);
+    for (int i = 0; i < aa.length; i++) {
+      expectEquals(aa[i], bb.charAt(i));
+    }
+
     System.out.println("passed");
   }