Initial implementation of .NETStandard 2.0 StackTrace / StackFrame API

This change supplies initial functional implementations of the .NET Standard 2.0 API's in StackTrace, StackFrame and StackFrameExtensions; it also includes runtime provisions for optional retrieval of IL offset and MethodBase when available in the AOT runtime.

[tfs-changeset: 1666008]

3 files changed, 74 insertions, 5 deletions

diff --git a/src/System.Private.StackTraceGenerator/src/Internal/Dia/DiaInterfaces.cs b/src/System.Private.StackTraceGenerator/src/Internal/Dia/DiaInterfaces.cs
index d64921df8..017395cae 100644
--- a/src/System.Private.StackTraceGenerator/src/Internal/Dia/DiaInterfaces.cs
+++ b/src/System.Private.StackTraceGenerator/src/Internal/Dia/DiaInterfaces.cs
@@ -92,6 +92,18 @@ namespace Internal.StackGenerator.Dia
             enumLineNumbers = new IDiaEnumLineNumbers(_enumLineNumbers);
             return hr;
         }
+
+        public int FindILOffsetsByRVA(int rva, int length, out IDiaEnumLineNumbers enumLineNumbers)
+        {
+            enumLineNumbers = null;
+            IntPtr _enumLineNumbers;
+            int hr = S.StdCall<int>(GetVTableMember(46), Punk, rva, length, out _enumLineNumbers);
+            GC.KeepAlive(this);
+            if (hr != S_OK)
+                return hr;
+            enumLineNumbers = new IDiaEnumLineNumbers(_enumLineNumbers);
+            return hr;
+        }
     }
 
     internal sealed class IDiaEnumSymbols : ComInterface
diff --git a/src/System.Private.StackTraceGenerator/src/Internal/StackTraceGenerator/StackTraceGenerator.Unix.cs b/src/System.Private.StackTraceGenerator/src/Internal/StackTraceGenerator/StackTraceGenerator.Unix.cs
index ba5d6c32d..6fb2c5c23 100644
--- a/src/System.Private.StackTraceGenerator/src/Internal/StackTraceGenerator/StackTraceGenerator.Unix.cs
+++ b/src/System.Private.StackTraceGenerator/src/Internal/StackTraceGenerator/StackTraceGenerator.Unix.cs
@@ -27,5 +27,14 @@ namespace Internal.StackTraceGenerator
             lineNumber = 0;
             columnNumber = 0;
         }
+
+        /// <summary>
+        /// Makes reasonable effort to locate the IL offset within the current method.
+        /// </summary>
+        public static void TryGetILOffsetWithinMethod(IntPtr ip, out int ilOffset)
+        {
+            // CORERT-TODO: Implement StackTraceGenerator on Unix
+            ilOffset = StackFrame.OFFSET_UNKNOWN;
+        }
     }
 }
diff --git a/src/System.Private.StackTraceGenerator/src/Internal/StackTraceGenerator/StackTraceGenerator.Windows.cs b/src/System.Private.StackTraceGenerator/src/Internal/StackTraceGenerator/StackTraceGenerator.Windows.cs
index 0e7110707..c686b811c 100644
--- a/src/System.Private.StackTraceGenerator/src/Internal/StackTraceGenerator/StackTraceGenerator.Windows.cs
+++ b/src/System.Private.StackTraceGenerator/src/Internal/StackTraceGenerator/StackTraceGenerator.Windows.cs
@@ -5,6 +5,7 @@
 using System;
 using System.Text;
 using System.Diagnostics;
+using System.Reflection;
 using System.Runtime.InteropServices;
 using Internal.Runtime.Augments;
 using Internal.StackGenerator.Dia;
@@ -78,11 +79,33 @@ namespace Internal.StackTraceGenerator
             fileName = null;
             lineNumber = 0;
             columnNumber = 0;
-            int rva;
-            IDiaSession session = GetDiaSession(ip, out rva);
-            if (session == null)
-                return;
-            TryGetSourceLineInfo(session, rva, out fileName, out lineNumber, out columnNumber);
+            if (!IsDiaStackTraceResolutionDisabled())
+            {
+                int rva;
+                IDiaSession session = GetDiaSession(ip, out rva);
+                if (session != null)
+                {
+                    TryGetSourceLineInfo(session, rva, out fileName, out lineNumber, out columnNumber);
+                }
+            }
+        }
+
+        /// <summary>
+        /// Makes reasonable effort to find the IL offset corresponding to the given address within a method.
+        /// Returns StackFrame.OFFSET_UNKNOWN if not available.
+        /// </summary>
+        public static void TryGetILOffsetWithinMethod(IntPtr ip, out int ilOffset)
+        {
+            ilOffset = StackFrame.OFFSET_UNKNOWN;
+            if (!IsDiaStackTraceResolutionDisabled())
+            {
+                int rva;
+                IDiaSession session = GetDiaSession(ip, out rva);
+                if (session != null)
+                {
+                    TryGetILOffsetInfo(session, rva, out ilOffset);
+                }
+            }
         }
 
         //
@@ -213,6 +236,31 @@ namespace Internal.StackTraceGenerator
             }
         }
 
+        private static void TryGetILOffsetInfo(IDiaSession session, int rva, out int ilOffset)
+        {
+            IDiaEnumLineNumbers lineNumbers;
+            int hr = session.FindILOffsetsByRVA(rva, 1, out lineNumbers);
+            if (hr == S_OK)
+            {
+                int numLineNumbers;
+                hr = lineNumbers.Count(out numLineNumbers);
+                if (hr == S_OK && numLineNumbers > 0)
+                {
+                    IDiaLineNumber ln;
+                    hr = lineNumbers.Item(0, out ln);
+                    if (hr == S_OK)
+                    {
+                        hr = ln.LineNumber(out ilOffset);
+                        if (hr == S_OK)
+                        {
+                            return;
+                        }
+                    }
+                }
+            }
+            ilOffset = StackFrame.OFFSET_UNKNOWN;
+        }
+
         //
         // Generate the " in <filename>:line <line#>" section.
         //