Enable Tiered Compilation by default (#19525)

Enable Tiered Compilation by default

1) Changes the default state of the tiered compilation feature check to be ON BY DEFAULT
2) Removed comments about the source about this being a work in progress. Although it will surely continue to evolve and improve, remaining issues would be better tracked in our issue tracking system with the same default presumption as other runtime features - assume it works unless noted otherwise.
3) Adjusts a number of tests and automated scripts that made assumptions that the default setting of this feature is off.
4) Stop accepting the deprecated env var COMPLUS_EXPERIMENTAL_TieredCompilation. I'm not aware it has any remaining usage but if so we're going to find out.
5) Adjust config names for JitBench

12 files changed, 54 insertions, 64 deletions

diff --git a/Documentation/project-docs/clr-configuration-knobs.md b/Documentation/project-docs/clr-configuration-knobs.md
index 7a6c4e6879..732d9a6b9b 100644
--- a/Documentation/project-docs/clr-configuration-knobs.md
+++ b/Documentation/project-docs/clr-configuration-knobs.md
@@ -17,7 +17,7 @@ Name | Description | Type
 
 ## Environment/Registry Configuration Knobs
 
-This table was machine-generated using `clr-configuration-knobs.csx` script from repository commit [8611986](https://github.com/dotnet/coreclr/commit/861198647dc232ecaf05b4a8e2f10605e7a22537) on 4/30/2018. It might be out of date. To generate latest documentation run `{dotnet} csi clr-configuration-knobs.csx` from this file directory.
+This table was machine-generated using `clr-configuration-knobs.csx` script from repository commit [79aadb8](https://github.com/dotnet/coreclr/commit/79aadb8c6455e30065cbd817e3ec5b52d17f3dce) on 6/12/2018. It might be out of date. To generate latest documentation run `{dotnet} csi clr-configuration-knobs.csx` from this file directory.
 
 When using these configurations from environment variables, the variables need to have the `COMPlus_` prefix in their names. e.g. To set DumpJittedMethods to 1, add the environment variable `COMPlus_DumpJittedMethods=1`.
 
@@ -769,8 +769,7 @@ Name | Description | Type | Class | Default Value | Flags
 
 Name | Description | Type | Class | Default Value | Flags 
 -----|-------------|------|-------|---------------|-------
-`EXPERIMENTAL_TieredCompilation` | Deprecated - Use COMPLUS_TieredCompilation | `DWORD` | `UNSUPPORTED` | `0` | 
-`TieredCompilation` | Enables tiered compilation | `DWORD` | `EXTERNAL` | `0` | 
+`TieredCompilation` | Enables tiered compilation | `DWORD` | `EXTERNAL` | `1` | 
 `TieredCompilation_Test_CallCounting` | Enabled by default (only activates when TieredCompilation is also enabled). If disabled immediately backpatches prestub, and likely prevents any tier1 promotion | `DWORD` | `UNSUPPORTED` | `1` | 
 `TieredCompilation_Test_OptimizeTier0` | Use optimized codegen (normally used by tier1) in tier0 | `DWORD` | `UNSUPPORTED` | `0` | 
 `TieredCompilation_Tier1CallCountingDelayMs` | Delay in milliseconds since process startup or the last tier 0 JIT before call counting begins for tier 1 promotion. | `DWORD` | `UNSUPPORTED` | `100` | 
diff --git a/src/inc/clrconfigvalues.h b/src/inc/clrconfigvalues.h
index e0cad9d962..0d843fbade 100644
--- a/src/inc/clrconfigvalues.h
+++ b/src/inc/clrconfigvalues.h
@@ -651,8 +651,7 @@ RETAIL_CONFIG_DWORD_INFO(INTERNAL_HillClimbing_GainExponent,
 /// Tiered Compilation
 ///
 #ifdef FEATURE_TIERED_COMPILATION
-RETAIL_CONFIG_DWORD_INFO(EXTERNAL_TieredCompilation, W("TieredCompilation"), 0, "Enables tiered compilation")
-RETAIL_CONFIG_DWORD_INFO(UNSUPPORTED_LEGACY_TieredCompilation, W("EXPERIMENTAL_TieredCompilation"), 0, "Deprecated - Use COMPLUS_TieredCompilation")
+RETAIL_CONFIG_DWORD_INFO(EXTERNAL_TieredCompilation, W("TieredCompilation"), 1, "Enables tiered compilation")
 RETAIL_CONFIG_DWORD_INFO(UNSUPPORTED_TieredCompilation_Tier1CallCountThreshold, W("TieredCompilation_Tier1CallCountThreshold"), 30, "Number of times a method must be called after which it is promoted to tier 1.")
 RETAIL_CONFIG_DWORD_INFO(UNSUPPORTED_TieredCompilation_Tier1CallCountingDelayMs, W("TieredCompilation_Tier1CallCountingDelayMs"), 100, "A perpetual delay in milliseconds that is applied to tier 1 call counting and jitting, while there is tier 0 activity.")
 RETAIL_CONFIG_DWORD_INFO(UNSUPPORTED_TieredCompilation_Tier1DelaySingleProcMultiplier, W("TieredCompilation_Tier1DelaySingleProcMultiplier"), 10, "Multiplier for TieredCompilation_Tier1CallCountingDelayMs that is applied on a single-processor machine or when the process is affinitized to a single processor.")
diff --git a/src/vm/eeconfig.cpp b/src/vm/eeconfig.cpp
index 41f80d8ba3..37864f1f83 100644
--- a/src/vm/eeconfig.cpp
+++ b/src/vm/eeconfig.cpp
@@ -1237,9 +1237,7 @@ HRESULT EEConfig::sync()
     dwSleepOnExit = CLRConfig::GetConfigValue(CLRConfig::UNSUPPORTED_SleepOnExit);
 
 #if defined(FEATURE_TIERED_COMPILATION)
-    fTieredCompilation = Configuration::GetKnobBooleanValue(W("System.Runtime.TieredCompilation"), CLRConfig::EXTERNAL_TieredCompilation) ||
-        //this older name is deprecated, but still accepted for a time. Preserving it is a very small overhead not to needlessly break things.
-        CLRConfig::GetConfigValue(CLRConfig::UNSUPPORTED_LEGACY_TieredCompilation) != 0;
+    fTieredCompilation = Configuration::GetKnobBooleanValue(W("System.Runtime.TieredCompilation"), CLRConfig::EXTERNAL_TieredCompilation) != 0;
 
     fTieredCompilation_CallCounting = CLRConfig::GetConfigValue(CLRConfig::UNSUPPORTED_TieredCompilation_Test_CallCounting) != 0;
     fTieredCompilation_OptimizeTier0 = CLRConfig::GetConfigValue(CLRConfig::UNSUPPORTED_TieredCompilation_Test_OptimizeTier0) != 0;
diff --git a/src/vm/tieredcompilation.cpp b/src/vm/tieredcompilation.cpp
index 7945973aa9..9c9e76de18 100644
--- a/src/vm/tieredcompilation.cpp
+++ b/src/vm/tieredcompilation.cpp
@@ -20,15 +20,6 @@
 // handles logistics of getting new code created and installed.
 //
 //
-// # Current feature state
-//
-// This feature is a work in progress. It should be functionally correct for a 
-// good range of scenarios, but performance varies by scenario. To enable it
-// you need to set COMPLUS_TieredCompilation = 1. This feature has been
-// tested with all of our runtime and CoreFX functional tests, as well as
-// diagnostics tests and various partner testing in Visual Studio. 
-//
-//
 // # Important entrypoints in this code:
 //
 // 
diff --git a/tests/runtest.cmd b/tests/runtest.cmd
index bb97cbd592..fb19439527 100644
--- a/tests/runtest.cmd
+++ b/tests/runtest.cmd
@@ -84,6 +84,7 @@ if /i "%1" == "CoreFXTestsAll"        (set __CoreFXTests=true&set __CoreFXTestsR
 if /i "%1" == "CoreFXTestList"        (set __CoreFXTests=true&set __CoreFXTestList=%2&shift&shift&goto Arg_Loop)
 if /i "%1" == "runcrossgentests"      (set RunCrossGen=true&shift&goto Arg_Loop)
 if /i "%1" == "link"                  (set DoLink=true&set ILLINK=%2&shift&shift&goto Arg_Loop)
+REM tieredcompilation is on by default now, but setting this environment variable is harmless and I didn't want to break any automation that might be using it just yet
 if /i "%1" == "tieredcompilation"     (set COMPLUS_TieredCompilation=1&shift&goto Arg_Loop)
 if /i "%1" == "gcname"                (set COMPlus_GCName=%2&shift&shift&goto Arg_Loop)
 if /i "%1" == "timeout"               (set __TestTimeout=%2&shift&shift&goto Arg_Loop)
diff --git a/tests/scripts/run-xunit-perf.py b/tests/scripts/run-xunit-perf.py
index 18a0b8e446..ac5de7b30e 100755
--- a/tests/scripts/run-xunit-perf.py
+++ b/tests/scripts/run-xunit-perf.py
@@ -457,8 +457,9 @@ def main(args):
     # Set up environment for running tests
     if optLevel == 'min_opts':
         myEnv['COMPlus_JITMinOpts'] = '1'
-    elif optLevel == 'tiered':
-        myEnv['COMPLUS_TieredCompilation'] = '1'
+        myEnv['COMPLUS_TieredCompilation'] = '0'
+    elif optLevel == 'full_opt':
+        myEnv['COMPLUS_TieredCompilation'] = '0'
 
     if not 'XUNIT_PERFORMANCE_MAX_ITERATION' in myEnv:
         myEnv['XUNIT_PERFORMANCE_MAX_ITERATION'] = '21'
diff --git a/tests/src/CLRTest.Execute.Bash.targets b/tests/src/CLRTest.Execute.Bash.targets
index a3fecb22a4..5560447363 100644
--- a/tests/src/CLRTest.Execute.Bash.targets
+++ b/tests/src/CLRTest.Execute.Bash.targets
@@ -81,11 +81,17 @@ then
   exit $(GCBashScriptExitCode)
 fi
       ]]></BashCLRTestEnvironmentCompatibilityCheck>
-      <BashCLRTestEnvironmentCompatibilityCheck Condition="'$(JitOptimizationSensitive)' == 'true'"><![CDATA[
+      <BashCLRTestEnvironmentCompatibilityCheck Condition="'$(JitOptimizationSensitive)' == 'true'">
+    <![CDATA[
 $(BashCLRTestEnvironmentCompatibilityCheck)
-if [[ ( ! -z "$COMPlus_JitStress" ) || ( ! -z "$COMPlus_JitStressRegs" ) || ( ! -z "$COMPlus_JITMinOpts" ) || ( ! -z "$COMPlus_TailcallStress" ) || ( ! -z "$COMPlus_EXPERIMENTAL_TieredCompilation" ) || ( ! -z "$COMPlus_TieredCompilation" ) ]]
+if [[ ( ! -z "$COMPlus_JitStress" ) || ( ! -z "$COMPlus_JitStressRegs" ) || ( ! -z "$COMPlus_JITMinOpts" ) || ( ! -z "$COMPlus_TailcallStress" ) ]]
+then
+  echo "SKIPPING EXECUTION BECAUSE ONE OR MORE OF (COMPlus_JitStress, COMPlus_JitStressRegs, COMPlus_JITMinOpts, COMPlus_TailcallStress) IS SET"
+  exit $(GCBashScriptExitCode)
+fi
+if [[ "$COMPlus_TieredCompilation" != "0" ]]
 then
-  echo "SKIPPING EXECUTION BECAUSE ONE OR MORE OF (COMPlus_JitStress, COMPlus_JitStressRegs, COMPlus_JITMinOpts, COMPlus_TailcallStress, COMPlus_EXPERIMENTAL_TieredCompilation, COMPlus_TieredCompilation) IS SET"
+  echo "SKIPPING EXECUTION BECAUSE COMPlus_TieredCompilation has not been disabled and this test is marked JitOptimizationSensitive"
   exit $(GCBashScriptExitCode)
 fi
       ]]></BashCLRTestEnvironmentCompatibilityCheck>
diff --git a/tests/src/CLRTest.Execute.Batch.targets b/tests/src/CLRTest.Execute.Batch.targets
index 70cede618f..4407010de4 100644
--- a/tests/src/CLRTest.Execute.Batch.targets
+++ b/tests/src/CLRTest.Execute.Batch.targets
@@ -76,13 +76,19 @@ IF NOT "%COMPlus_GCStress%"=="" (
   Exit /b 0
 )
       ]]></BatchCLRTestEnvironmentCompatibilityCheck>
-      <BatchCLRTestEnvironmentCompatibilityCheck Condition="'$(JitOptimizationSensitive)' == 'true'"><![CDATA[
+      <BatchCLRTestEnvironmentCompatibilityCheck Condition="'$(JitOptimizationSensitive)' == 'true'">
+    <![CDATA[
 $(BatchCLRTestEnvironmentCompatibilityCheck)
-IF "%COMPlus_JitStress%"=="" IF "%COMPlus_JitStressRegs%"=="" IF "%COMPlus_JITMinOpts%"=="" IF "%COMPlus_TailcallStress%"=="" IF "%COMPlus_EXPERIMENTAL_TieredCompilation%"=="" IF "%COMPlus_TieredCompilation%"=="" goto :Compatible1
-  ECHO SKIPPING EXECUTION BECAUSE ONE OR MORE OF (COMPlus_JitStress, COMPlus_JitStressRegs, COMPlus_JITMinOpts, COMPlus_TailcallStress, COMPlus_EXPERIMENTAL_TieredCompilation, COMPlus_TieredCompilation) IS SET
+IF "%COMPlus_JitStress%"=="" IF "%COMPlus_JitStressRegs%"=="" IF "%COMPlus_JITMinOpts%"=="" IF "%COMPlus_TailcallStress%"=="" IF "%COMPlus_TieredCompilation%"=="" goto :Compatible1
+  ECHO SKIPPING EXECUTION BECAUSE ONE OR MORE OF (COMPlus_JitStress, COMPlus_JitStressRegs, COMPlus_JITMinOpts, COMPlus_TailcallStress, COMPlus_TieredCompilation) IS SET
   popd
   Exit /b 0
 :Compatible1
+IF "%COMPlus_TieredCompilation%"=="0" goto :Compatible2
+  ECHO SKIPPING EXECUTION BECAUSE COMPlus_TieredCompilation has not been disabled and this test is marked JitOptimizationSensitive
+  popd
+  Exit /b 0
+:Compatible2
       ]]></BatchCLRTestEnvironmentCompatibilityCheck>
       <BatchCLRTestEnvironmentCompatibilityCheck Condition="'$(HeapVerifyIncompatible)' == 'true'"><![CDATA[
 $(BatchCLRTestEnvironmentCompatibilityCheck)
diff --git a/tests/src/baseservices/exceptions/stacktrace/Tier1StackTrace.csproj b/tests/src/baseservices/exceptions/stacktrace/Tier1StackTrace.csproj
index c0a2ca94b0..e08ec1dc0a 100644
--- a/tests/src/baseservices/exceptions/stacktrace/Tier1StackTrace.csproj
+++ b/tests/src/baseservices/exceptions/stacktrace/Tier1StackTrace.csproj
@@ -19,15 +19,5 @@
   <ItemGroup>
     <Compile Include="Tier1StackTrace.cs" />
   </ItemGroup>
-  <PropertyGroup>
-    <CLRTestBatchPreCommands><![CDATA[
-$(CLRTestBatchPreCommands)
-set COMPlus_TieredCompilation=1
-]]></CLRTestBatchPreCommands>
-    <BashCLRTestPreCommands><![CDATA[
-$(BashCLRTestPreCommands)
-export COMPlus_TieredCompilation=1
-]]></BashCLRTestPreCommands>
-  </PropertyGroup>
   <Import Project="$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildThisFileDirectory), dir.targets))\dir.targets" />
 </Project>
diff --git a/tests/src/performance/Scenario/JitBench/Runner/BenchmarkConfiguration.cs b/tests/src/performance/Scenario/JitBench/Runner/BenchmarkConfiguration.cs
index 7043489fa5..bdc8ac7dad 100644
--- a/tests/src/performance/Scenario/JitBench/Runner/BenchmarkConfiguration.cs
+++ b/tests/src/performance/Scenario/JitBench/Runner/BenchmarkConfiguration.cs
@@ -11,22 +11,19 @@ namespace JitBench
             Name = "Default";
             EnvironmentVariables = new Dictionary<string, string>();
         }
+
         public bool IsDefault {  get { return Name == "Default"; } }
         public string Name { get; set; }
         public Dictionary<string, string> EnvironmentVariables { get; private set; }
 
-        public BenchmarkConfiguration WithTiering()
+        public BenchmarkConfiguration WithoutTiering()
         {
-            return WithModifier("Tiering", "COMPLUS_TieredCompilation", "1");
+            return WithModifier("NoTiering", "COMPlus_TieredCompilation", "0");
         }
 
         public BenchmarkConfiguration WithMinOpts()
         {
-            BenchmarkConfiguration configuration =
-                WithModifier("Minopts", "COMPLUS_JitMinOpts", "1").
-                WithModifier("Tiering", "COMPLUS_TieredCompilation", "0");
-            configuration.Name = "Minopts";
-            return configuration;
+            return WithModifier("Minopts", "COMPlus_JitMinOpts", "1");
         }
 
         public BenchmarkConfiguration WithNoR2R()
@@ -36,7 +33,7 @@ namespace JitBench
 
         public BenchmarkConfiguration WithNoNgen()
         {
-            return WithModifier("NoNgen", "COMPLUS_ZapDisable", "1");
+            return WithModifier("NoNgen", "COMPlus_ZapDisable", "1");
         }
 
         private BenchmarkConfiguration WithModifier(string modifier, string variableName, string variableValue)
diff --git a/tests/src/performance/Scenario/JitBench/Runner/Program.cs b/tests/src/performance/Scenario/JitBench/Runner/Program.cs
index fc8615dbf8..bd664e1e23 100644
--- a/tests/src/performance/Scenario/JitBench/Runner/Program.cs
+++ b/tests/src/performance/Scenario/JitBench/Runner/Program.cs
@@ -163,24 +163,24 @@ namespace JitBench
 
         static IEnumerable<BenchmarkConfiguration> GetBenchmarkConfigurations(CommandLineOptions options)
         {
-            string tieredEnv = Environment.GetEnvironmentVariable("COMPLUS_TieredCompilation");
-            string minoptsEnv = Environment.GetEnvironmentVariable("COMPLUS_JitMinopts");
-            string r2rEnv = Environment.GetEnvironmentVariable("COMPLUS_ReadyToRun");
-            string ngenEnv = Environment.GetEnvironmentVariable("COMPLUS_ZapDisable");
+            string tieredEnv = Environment.GetEnvironmentVariable("COMPlus_TieredCompilation");
+            string minoptsEnv = Environment.GetEnvironmentVariable("COMPlus_JitMinopts");
+            string r2rEnv = Environment.GetEnvironmentVariable("COMPlus_ReadyToRun");
+            string noNgenEnv = Environment.GetEnvironmentVariable("COMPlus_ZapDisable");
             BenchmarkConfiguration envConfig = new BenchmarkConfiguration();
-            if(tieredEnv != null && tieredEnv != "0")
+            if(tieredEnv != null && tieredEnv == "0")
             {
-                envConfig.WithTiering();
+                envConfig.WithoutTiering();
             }
             if (minoptsEnv != null && minoptsEnv != "0")
             {
                 envConfig.WithMinOpts();
             }
-            if(r2rEnv != null && r2rEnv != "1")
+            if(r2rEnv != null && r2rEnv == "0")
             {
                 envConfig.WithNoR2R();
             }
-            if(ngenEnv != null && ngenEnv != "0")
+            if(noNgenEnv != null && noNgenEnv != "0")
             {
                 envConfig.WithNoNgen();
             }
@@ -196,13 +196,25 @@ namespace JitBench
                 yield break;
             }
 
+            // The minopts config name by itself implies without tiering
+            var minOptsConfig = new BenchmarkConfiguration().WithMinOpts();
+            string minOptsConfigName = minOptsConfig.Name;
+            minOptsConfig = minOptsConfig.WithoutTiering();
+            minOptsConfig.Name = minOptsConfigName;
+
             BenchmarkConfiguration[] possibleConfigs = new BenchmarkConfiguration[]
             {
                 new BenchmarkConfiguration(),
-                new BenchmarkConfiguration().WithTiering(),
-                new BenchmarkConfiguration().WithMinOpts(),
+                new BenchmarkConfiguration().WithoutTiering(),
+                minOptsConfig,
+                new BenchmarkConfiguration().WithMinOpts().WithoutTiering(),
+                new BenchmarkConfiguration().WithoutTiering().WithMinOpts(),
                 new BenchmarkConfiguration().WithNoR2R(),
-                new BenchmarkConfiguration().WithNoNgen()
+                new BenchmarkConfiguration().WithNoR2R().WithoutTiering(),
+                new BenchmarkConfiguration().WithoutTiering().WithNoR2R(),
+                new BenchmarkConfiguration().WithNoNgen(),
+                new BenchmarkConfiguration().WithNoNgen().WithoutTiering(),
+                new BenchmarkConfiguration().WithoutTiering().WithNoNgen()
             };
             foreach(string configName in configNames)
             {
diff --git a/tests/src/reflection/Tier1Collectible/Tier1Collectible.csproj b/tests/src/reflection/Tier1Collectible/Tier1Collectible.csproj
index 926be4a475..f77c7cff63 100644
--- a/tests/src/reflection/Tier1Collectible/Tier1Collectible.csproj
+++ b/tests/src/reflection/Tier1Collectible/Tier1Collectible.csproj
@@ -18,15 +18,5 @@
   <ItemGroup>
     <Compile Include="Tier1Collectible.cs" />
   </ItemGroup>
-  <PropertyGroup>
-    <CLRTestBatchPreCommands><![CDATA[
-$(CLRTestBatchPreCommands)
-set COMPlus_TieredCompilation=1
-]]></CLRTestBatchPreCommands>
-    <BashCLRTestPreCommands><![CDATA[
-$(BashCLRTestPreCommands)
-export COMPlus_TieredCompilation=1
-]]></BashCLRTestPreCommands>
-  </PropertyGroup>
   <Import Project="$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildThisFileDirectory), dir.targets))\dir.targets" />
 </Project>