#endif // DEBUG
}
+//------------------------------------------------------------------------
+// fgGetHandlerLiveVars: determine set of locals live because of implicit
+// exception flow from a block.
+//
+// Arguments:
+// block - the block in question
+//
+// Returns:
+// Additional set of locals to be considered live throughout the block.
+//
+// Notes:
+// Assumes caller has screened candidate blocks to only those with
+// exception flow, via `ehBlockHasExnFlowDsc`.
+//
+// Exception flow can arise because of a newly raised exception (for
+// blocks within try regions) or because of an actively propagating exception
+// (for filter blocks). This flow effectively creates additional successor
+// edges in the flow graph that the jit does not model. This method computes
+// the net contribution from all the missing successor edges.
+//
+// For example, with the following C# source, during EH processing of the throw,
+// the outer filter will execute in pass1, before the inner handler executes
+// in pass2, and so the filter blocks should show the inner handler's local is live.
+//
+// try
+// {
+// using (AllocateObject()) // ==> try-finally; handler calls Dispose
+// {
+// throw new Exception();
+// }
+// }
+// catch (Exception e1) when (IsExpectedException(e1))
+// {
+// Console.WriteLine("In catch 1");
+// }
+
VARSET_VALRET_TP Compiler::fgGetHandlerLiveVars(BasicBlock* block)
{
noway_assert(block);
do
{
/* Either we enter the filter first or the catch/finally */
-
if (HBtab->HasFilter())
{
VarSetOps::UnionD(this, liveVars, HBtab->ebdFilter->bbLiveIn);
} while (true);
+ // If this block is within a filter, we also need to report as live
+ // any vars live into enclosed finally or fault handlers, since the
+ // filter will run during the first EH pass, and enclosed or enclosing
+ // handlers will run during the second EH pass. So all these handlers
+ // are "exception flow" successors of the filter.
+ //
+ // Note we are relying on ehBlockHasExnFlowDsc to return true
+ // for any filter block that we should examine here.
+ if (block->hasHndIndex())
+ {
+ const unsigned thisHndIndex = block->getHndIndex();
+ EHblkDsc* enclosingHBtab = ehGetDsc(thisHndIndex);
+
+ if (enclosingHBtab->InFilterRegionBBRange(block))
+ {
+ assert(enclosingHBtab->HasFilter());
+
+ // Search the EH table for enclosed regions.
+ //
+ // All the enclosed regions will be lower numbered and
+ // immediately prior to and contiguous with the enclosing
+ // region in the EH tab.
+ unsigned index = thisHndIndex;
+
+ while (index > 0)
+ {
+ index--;
+ unsigned enclosingIndex = ehGetEnclosingTryIndex(index);
+ bool isEnclosed = false;
+
+ // To verify this is an enclosed region, search up
+ // through the enclosing regions until we find the
+ // region associated with the filter.
+ while (enclosingIndex != EHblkDsc::NO_ENCLOSING_INDEX)
+ {
+ if (enclosingIndex == thisHndIndex)
+ {
+ isEnclosed = true;
+ break;
+ }
+
+ enclosingIndex = ehGetEnclosingTryIndex(enclosingIndex);
+ }
+
+ // If we found an enclosed region, check if the region
+ // is a try fault or try finally, and if so, add any
+ // locals live into the enclosed region's handler into this
+ // block's live-in set.
+ if (isEnclosed)
+ {
+ EHblkDsc* enclosedHBtab = ehGetDsc(index);
+
+ if (enclosedHBtab->HasFinallyOrFaultHandler())
+ {
+ VarSetOps::UnionD(this, liveVars, enclosedHBtab->ebdHndBeg->bbLiveIn);
+ }
+ }
+ // Once we run across a non-enclosed region, we can stop searching.
+ else
+ {
+ break;
+ }
+ }
+ }
+ }
+
return liveVars;
}
// since (without proof otherwise) the use and def may touch different memory at run-time.
m_memoryLiveIn = m_memoryLiveOut | block->bbMemoryUse;
- /* Can exceptions from this block be handled (in this function)? */
-
+ // Does this block have implicit exception flow to a filter or handler?
+ // If so, include the effects of that flow.
if (m_compiler->ehBlockHasExnFlowDsc(block))
{
const VARSET_TP& liveVars(m_compiler->fgGetHandlerLiveVars(block));
-
VarSetOps::UnionD(m_compiler, m_liveIn, liveVars);
VarSetOps::UnionD(m_compiler, m_liveOut, liveVars);
+
+ // Implicit eh edges can induce loop-like behavior,
+ // so make sure we iterate to closure.
+ m_hasPossibleBackEdge = true;
}
/* Has there been any change in either live set? */
if (block->bbCatchTyp != BBCT_NONE)
{
/* Note the set of variables live on entry to exception handler */
-
VarSetOps::UnionD(this, exceptVars, block->bbLiveIn);
}
--- /dev/null
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+
+// Repro for issue 22820. On x86 we need to report enclosed handler
+// live-in locals as live into any enclosing filter.
+//
+// Run with optimized codegen and COMPlus_GCStress=0x4
+
+class DisposableObject : IDisposable
+{
+ public void Dispose()
+ {
+ Console.WriteLine("In dispose");
+ }
+}
+
+class Program
+{
+ public static bool IsExpectedException(Exception e)
+ {
+ Console.WriteLine("In filter");
+ GC.Collect();
+ return e is OperationCanceledException;
+ }
+
+ public static IDisposable AllocateObject()
+ {
+ return new DisposableObject();
+ }
+
+ static int Main(string[] args)
+ {
+ int result = 0;
+
+ try
+ {
+ try
+ {
+ using (AllocateObject())
+ {
+ throw new Exception();
+ }
+ }
+ catch (Exception e1) when (IsExpectedException(e1))
+ {
+ Console.WriteLine("In catch 1");
+ }
+ }
+ catch (Exception e2)
+ {
+ Console.WriteLine("In catch 2");
+ result = 100;
+ }
+
+ return result;
+ }
+}
--- /dev/null
+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="12.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+ <Import Project="$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildThisFileDirectory), dir.props))\dir.props" />
+ <PropertyGroup>
+ <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
+ <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
+ <SchemaVersion>2.0</SchemaVersion>
+ <ProjectGuid>{2649FAFE-07BF-4F93-8120-BA9A69285ABB}</ProjectGuid>
+ <OutputType>Exe</OutputType>
+ <ProjectTypeGuids>{786C830F-07A1-408B-BD7F-6EE04809D6DB};{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}</ProjectTypeGuids>
+ <SolutionDir Condition="$(SolutionDir) == '' Or $(SolutionDir) == '*Undefined*'">..\..\</SolutionDir>
+ </PropertyGroup>
+ <!-- Default configurations to help VS understand the configurations -->
+ <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' "></PropertyGroup>
+ <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' "></PropertyGroup>
+ <PropertyGroup>
+ <DebugType>None</DebugType>
+ <Optimize>True</Optimize>
+ </PropertyGroup>
+ <ItemGroup>
+ <CodeAnalysisDependentAssemblyPaths Condition=" '$(VS100COMNTOOLS)' != '' " Include="$(VS100COMNTOOLS)..\IDE\PrivateAssemblies">
+ <Visible>False</Visible>
+ </CodeAnalysisDependentAssemblyPaths>
+ </ItemGroup>
+ <ItemGroup>
+ <Service Include="{82A7F48D-3B50-4B1E-B82E-3ADA8210C358}" />
+ </ItemGroup>
+ <ItemGroup>
+ <Compile Include="$(MSBuildProjectName).cs" />
+ </ItemGroup>
+ <Import Project="$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildThisFileDirectory), dir.targets))\dir.targets" />
+ <PropertyGroup Condition=" '$(MsBuildProjectDirOverride)' != '' "></PropertyGroup>
+</Project>
\ No newline at end of file
projects / platform / upstream / coreclr.git / commitdiff