Don't use predicated vectorization by default.

This patch sets the traditional vectorization mode to be
the default one; previously, if the target supported
predicated vectorization (e.g. arm64 SVE), predicated
vectorization was be tried for ALL loops.

Motivation: this is a prerequisite for the further patches
to enable mixed mode vectorization - when most of the loops
are vectorized in traditional mode and some others - in
predicated.

A new env variable - ART_FORCE_TRY_PREDICATED_SIMD - is
introduced to force-use the predicated mode; this could be
set to true for testing purposes.

Checker tests are adjusted accordingly - to also check the
ART_FORCE_TRY_PREDICATED_SIMD variable.

Test: test-art-target, test-art-host.
Test: test-art-target with ART_FORCE_TRY_PREDICATED_SIMD=true.

Original author: Artem Serov <Artem.Serov@linaro.org>

Test: ./art/test/testrunner/testrunner.py --host --optimizing --jit
Test: ./art/test/testrunner/testrunner.py --target --optimizing --jit
      (with ART_FORCE_TRY_PREDICATED_SIMD=true and without)

Test: 661-checker-simd-cf-loops.
Test: target tests on arm64 with SVE
Change-Id: I57852f3777da6f86d615429d1a3c703cb87fbac8

1 files changed, 10 insertions, 10 deletions

diff --git a/test/623-checker-loop-regressions/src/Main.java b/test/623-checker-loop-regressions/src/Main.java
index 2b280bb7d6..134e90c6c5 100644
--- a/test/623-checker-loop-regressions/src/Main.java
+++ b/test/623-checker-loop-regressions/src/Main.java
@@ -290,7 +290,7 @@ public class Main {
   /// CHECK-NOT: VecLoad
   //
   /// CHECK-START-ARM64: void Main.string2Bytes(char[], java.lang.String) loop_optimization (after)
-  /// CHECK-IF:     hasIsaFeature("sve")
+  /// CHECK-IF:     hasIsaFeature("sve") and os.environ.get('ART_FORCE_TRY_PREDICATED_SIMD') == 'true'
   //
   //      TODO: Support CharAt for SVE.
   ///     CHECK-NOT: VecLoad
@@ -314,7 +314,7 @@ public class Main {
   /// CHECK-NOT: VecLoad
 
   /// CHECK-START-ARM64: void Main.$noinline$stringToShorts(short[], java.lang.String) loop_optimization (after)
-  /// CHECK-IF:     hasIsaFeature("sve")
+  /// CHECK-IF:     hasIsaFeature("sve") and os.environ.get('ART_FORCE_TRY_PREDICATED_SIMD') == 'true'
   //
   //      TODO: Support CharAt for SVE.
   ///     CHECK-NOT: VecLoad
@@ -368,7 +368,7 @@ public class Main {
   //
   /// CHECK-START-ARM64: void Main.oneBoth(short[], char[]) loop_optimization (after)
   /// CHECK-DAG: <<One:i\d+>>  IntConstant 1                             loop:none
-  /// CHECK-IF:     hasIsaFeature("sve")
+  /// CHECK-IF:     hasIsaFeature("sve") and os.environ.get('ART_FORCE_TRY_PREDICATED_SIMD') == 'true'
   //
   ///     CHECK-DAG: <<Repl:d\d+>>  VecReplicateScalar [<<One>>,{{j\d+}}]               loop:none
   ///     CHECK-DAG: <<LoopP:j\d+>> VecPredWhile                                        loop:<<Loop:B\d+>> outer_loop:none
@@ -423,7 +423,7 @@ public class Main {
   //
   /// CHECK-START-ARM64: void Main.typeConv(byte[], byte[]) loop_optimization (after)
   /// CHECK-DAG: <<One:i\d+>>  IntConstant 1                         loop:none
-  /// CHECK-IF:     hasIsaFeature("sve")
+  /// CHECK-IF:     hasIsaFeature("sve") and os.environ.get('ART_FORCE_TRY_PREDICATED_SIMD') == 'true'
   //
   ///     CHECK-DAG: <<Repl:d\d+>>  VecReplicateScalar [<<One>>,{{j\d+}}]           loop:none
   ///     CHECK-DAG: <<LoopP:j\d+>> VecPredWhile                                    loop:<<Loop1:B\d+>> outer_loop:none
@@ -765,7 +765,7 @@ public class Main {
   /// CHECK-DAG:       VecStore
   //
   /// CHECK-START-ARM64: int Main.testSADAndSet(int[], int[], int[]) loop_optimization (after)
-  /// CHECK-IF:     hasIsaFeature("sve")
+  /// CHECK-IF:     hasIsaFeature("sve") and os.environ.get('ART_FORCE_TRY_PREDICATED_SIMD') == 'true'
   //
   //      VecSADAccumulate is not supported for SVE.
   ///     CHECK-NOT:       VecSADAccumulate
@@ -793,7 +793,7 @@ public class Main {
   /// CHECK-DAG:       VecSADAccumulate
   //
   /// CHECK-START-ARM64: int Main.testSADAndSAD(int[], int[]) loop_optimization (after)
-  /// CHECK-IF:     hasIsaFeature("sve")
+  /// CHECK-IF:     hasIsaFeature("sve") and os.environ.get('ART_FORCE_TRY_PREDICATED_SIMD') == 'true'
   //
   //      VecSADAccumulate is not supported for SVE.
   ///     CHECK-NOT:       VecSADAccumulate
@@ -860,7 +860,7 @@ public class Main {
   /// CHECK-DAG:       VecSADAccumulate
   //
   /// CHECK-START-ARM64: int Main.testSADAndSADExtraAbs0(int[], int[]) loop_optimization (after)
-  /// CHECK-IF:     hasIsaFeature("sve")
+  /// CHECK-IF:     hasIsaFeature("sve") and os.environ.get('ART_FORCE_TRY_PREDICATED_SIMD') == 'true'
   //
   //      VecSADAccumulate is not supported for SVE.
   ///     CHECK-NOT:       VecSADAccumulate
@@ -894,7 +894,7 @@ public class Main {
   /// CHECK-DAG:       VecSADAccumulate
   //
   /// CHECK-START-ARM64: int Main.testSADAndSADExtraAbs1(int[], int[]) loop_optimization (after)
-  /// CHECK-IF:     hasIsaFeature("sve")
+  /// CHECK-IF:     hasIsaFeature("sve") and os.environ.get('ART_FORCE_TRY_PREDICATED_SIMD') == 'true'
   //
   //      VecSADAccumulate is not supported for SVE.
   ///     CHECK-NOT:       VecSADAccumulate
@@ -923,7 +923,7 @@ public class Main {
   // Idioms common sub-expression bug: SAD and DotProd combined.
   //
   /// CHECK-START-ARM64: int Main.testSADAndDotProdCombined0(byte[], byte[]) loop_optimization (after)
-  /// CHECK-IF:     hasIsaFeature("sve")
+  /// CHECK-IF:     hasIsaFeature("sve") and os.environ.get('ART_FORCE_TRY_PREDICATED_SIMD') == 'true'
   //
   //      VecSADAccumulate is not supported for SVE.
   ///     CHECK-NOT:       VecSADAccumulate
@@ -951,7 +951,7 @@ public class Main {
 
   // Idioms common sub-expression bug: SAD and DotProd combined (reversed order).
   /// CHECK-START-ARM64: int Main.testSADAndDotProdCombined1(byte[], byte[]) loop_optimization (after)
-  /// CHECK-IF:     hasIsaFeature("sve")
+  /// CHECK-IF:     hasIsaFeature("sve") and os.environ.get('ART_FORCE_TRY_PREDICATED_SIMD') == 'true'
   //
   //      VecSADAccumulate is not supported for SVE.
   ///     CHECK-NOT:       VecSADAccumulate