Improvements in induction range analysis.
Rationale:
Uses range analysis while determining whether trip-counts
are "safe", which improves analysis of triangular loops.
Also implements more effective triangular loop analysis
by evaluating induction information only once and using
a top level hint (instead of the "iterative refinement"
that was used earlier). Also fixes analysis of triangular
trip counts that may wrap-around. All with tests.
Test: see induction_var_range_test/530-checker-loops*
BUG=27151190
Change-Id: I1877c8ce0c9a52005900eb9dfdbb1918df100278
diff --git a/test/530-checker-loops1/src/Main.java b/test/530-checker-loops1/src/Main.java
index 948a7b7..dde4d62 100644
--- a/test/530-checker-loops1/src/Main.java
+++ b/test/530-checker-loops1/src/Main.java
@@ -562,7 +562,7 @@
//
/// CHECK-START: void Main.linearTriangularOnTwoArrayLengths(int) BCE (after)
/// CHECK-NOT: BoundsCheck
- // TODO: also CHECK-NOT: Deoptimize, see b/27151190
+ /// CHECK-NOT: Deoptimize
private static void linearTriangularOnTwoArrayLengths(int n) {
int[] a = new int[n];
for (int i = 0; i < a.length; i++) {
@@ -604,7 +604,7 @@
//
/// CHECK-START: void Main.linearTriangularOnParameter(int) BCE (after)
/// CHECK-NOT: BoundsCheck
- // TODO: also CHECK-NOT: Deoptimize, see b/27151190
+ /// CHECK-NOT: Deoptimize
private static void linearTriangularOnParameter(int n) {
int[] a = new int[n];
for (int i = 0; i < n; i++) {
@@ -619,56 +619,56 @@
}
}
- /// CHECK-START: void Main.linearTriangularVariationsInnerStrict(int) BCE (before)
+ /// CHECK-START: void Main.linearTriangularStrictLower(int) BCE (before)
/// CHECK-DAG: BoundsCheck
/// CHECK-DAG: BoundsCheck
/// CHECK-DAG: BoundsCheck
/// CHECK-DAG: BoundsCheck
//
- /// CHECK-START: void Main.linearTriangularVariationsInnerStrict(int) BCE (after)
+ /// CHECK-START: void Main.linearTriangularStrictLower(int) BCE (after)
/// CHECK-NOT: BoundsCheck
- // TODO: also CHECK-NOT: Deoptimize, see b/27151190
- private static void linearTriangularVariationsInnerStrict(int n) {
+ /// CHECK-NOT: Deoptimize
+ private static void linearTriangularStrictLower(int n) {
int[] a = new int[n];
for (int i = 0; i < n; i++) {
for (int j = 0; j < i; j++) {
a[j] += 1;
}
- for (int j = i - 1; j > -1; j--) {
+ for (int j = i - 1; j >= 0; j--) {
a[j] += 1;
}
for (int j = i; j < n; j++) {
a[j] += 1;
}
- for (int j = n - 1; j > i - 1; j--) {
+ for (int j = n - 1; j >= i; j--) {
a[j] += 1;
}
}
verifyTriangular(a);
}
- /// CHECK-START: void Main.linearTriangularVariationsInnerNonStrict(int) BCE (before)
+ /// CHECK-START: void Main.linearTriangularStrictUpper(int) BCE (before)
/// CHECK-DAG: BoundsCheck
/// CHECK-DAG: BoundsCheck
/// CHECK-DAG: BoundsCheck
/// CHECK-DAG: BoundsCheck
//
- /// CHECK-START: void Main.linearTriangularVariationsInnerNonStrict(int) BCE (after)
+ /// CHECK-START: void Main.linearTriangularStrictUpper(int) BCE (after)
/// CHECK-NOT: BoundsCheck
- // TODO: also CHECK-NOT: Deoptimize, see b/27151190
- private static void linearTriangularVariationsInnerNonStrict(int n) {
+ /// CHECK-NOT: Deoptimize
+ private static void linearTriangularStrictUpper(int n) {
int[] a = new int[n];
for (int i = 0; i < n; i++) {
- for (int j = 0; j <= i - 1; j++) {
+ for (int j = 0; j <= i; j++) {
a[j] += 1;
}
- for (int j = i - 1; j >= 0; j--) {
+ for (int j = i; j >= 0; j--) {
a[j] += 1;
}
- for (int j = i; j <= n - 1; j++) {
+ for (int j = i + 1; j < n; j++) {
a[j] += 1;
}
- for (int j = n - 1; j >= i; j--) {
+ for (int j = n - 1; j >= i + 1; j--) {
a[j] += 1;
}
}
@@ -802,8 +802,8 @@
linearTriangularOnTwoArrayLengths(10);
linearTriangularOnOneArrayLength(10);
linearTriangularOnParameter(10);
- linearTriangularVariationsInnerStrict(10);
- linearTriangularVariationsInnerNonStrict(10);
+ linearTriangularStrictLower(10);
+ linearTriangularStrictUpper(10);
{
int[] t = linearTriangularOOB();
for (int i = 0; i < 200; i++) {