[NativeAOT] A few cleanups in stack walking on Windows (#86917)

dotnet · Jun 4, 2023 · 2bf8f1a · 2bf8f1a
1 parent 48ce1d9
commit 2bf8f1a
Show file tree

Hide file tree

Showing 6 changed files with 36 additions and 21 deletions.
diff --git a/src/coreclr/nativeaot/Runtime.Base/src/System/RuntimeTypeHandle.cs b/src/coreclr/nativeaot/Runtime.Base/src/System/RuntimeTypeHandle.cs
@@ -18,6 +18,6 @@ public class Type
     [StructLayout(LayoutKind.Sequential)]
     public struct RuntimeTypeHandle
     {
-        private EETypePtr _pEEType;
+        private IntPtr _value;
     }
 }
diff --git a/src/coreclr/nativeaot/Runtime/ICodeManager.h b/src/coreclr/nativeaot/Runtime/ICodeManager.h
@@ -172,6 +172,8 @@ enum UnwindStackFrameFlags
     // If this is a reverse P/Invoke frame, do not continue the unwind
     // after extracting the saved transition frame.
     USFF_StopUnwindOnTransitionFrame = 1,
+    // Registers not containing GC roots can be omitted.
+    USFF_GcUnwind = 2,
 };
 
 class ICodeManager

diff --git a/src/coreclr/nativeaot/Runtime/StackFrameIterator.cpp b/src/coreclr/nativeaot/Runtime/StackFrameIterator.cpp
@@ -1442,6 +1442,11 @@ void StackFrameIterator::NextInternal()
         unwindFlags |= USFF_StopUnwindOnTransitionFrame;
     }
 
+    if ((m_dwFlags & GcStackWalkFlags) == GcStackWalkFlags)
+    {
+        unwindFlags |= USFF_GcUnwind;
+    }
+
     FAILFAST_OR_DAC_FAIL(GetCodeManager()->UnwindStackFrame(&m_methodInfo, unwindFlags, &m_RegDisplay,
                                                             &m_pPreviousTransitionFrame));
 

diff --git a/src/coreclr/nativeaot/Runtime/windows/CoffNativeCodeManager.cpp b/src/coreclr/nativeaot/Runtime/windows/CoffNativeCodeManager.cpp
@@ -590,9 +590,9 @@ bool CoffNativeCodeManager::UnwindStackFrame(MethodInfo *    pMethodInfo,
     #define WORDPTR PDWORD
 #elif defined(TARGET_AMD64)
     #define FOR_EACH_NONVOLATILE_REGISTER(F) \
-        F(Rax, pRax) F(Rcx, pRcx) F(Rdx, pRdx) F(Rbx, pRbx) F(Rbp, pRbp) F(Rsi, pRsi) F(Rdi, pRdi) \
-        F(R8, pR8) F(R9, pR9) F(R10, pR10) F(R11, pR11) F(R12, pR12) F(R13, pR13) F(R14, pR14) F(R15, pR15)
-    #define WORDPTR PDWORD64
+        F(Rbx, pRbx) F(Rbp, pRbp) F(Rsi, pRsi) F(Rdi, pRdi) \
+        F(R12, pR12) F(R13, pR13) F(R14, pR14) F(R15, pR15)
+#define WORDPTR PDWORD64
 #elif defined(TARGET_ARM64)
     #define FOR_EACH_NONVOLATILE_REGISTER(F) \
         F(X19, pX19) F(X20, pX20) F(X21, pX21) F(X22, pX22) F(X23, pX23) F(X24, pX24) \
@@ -612,7 +612,11 @@ bool CoffNativeCodeManager::UnwindStackFrame(MethodInfo *    pMethodInfo,
 #if defined(TARGET_X86)
     PORTABILITY_ASSERT("CoffNativeCodeManager::UnwindStackFrame");
 #elif defined(TARGET_AMD64)
-    memcpy(&context.Xmm6, pRegisterSet->Xmm, sizeof(pRegisterSet->Xmm));
+
+    if (!(flags & USFF_GcUnwind))
+    {
+        memcpy(&context.Xmm6, pRegisterSet->Xmm, sizeof(pRegisterSet->Xmm));
+    }
 
     context.Rsp = pRegisterSet->SP;
     context.Rip = pRegisterSet->IP;
@@ -634,10 +638,16 @@ bool CoffNativeCodeManager::UnwindStackFrame(MethodInfo *    pMethodInfo,
 
     pRegisterSet->pIP = PTR_PCODE(pRegisterSet->SP - sizeof(TADDR));
 
-    memcpy(pRegisterSet->Xmm, &context.Xmm6, sizeof(pRegisterSet->Xmm));
+    if (!(flags & USFF_GcUnwind))
+    {
+        memcpy(pRegisterSet->Xmm, &context.Xmm6, sizeof(pRegisterSet->Xmm));
+    }
 #elif defined(TARGET_ARM64)
-    for (int i = 8; i < 16; i++)
-        context.V[i].Low = pRegisterSet->D[i - 8];
+    if (!(flags & USFF_GcUnwind))
+    {
+        for (int i = 8; i < 16; i++)
+            context.V[i].Low = pRegisterSet->D[i - 8];
+    }
 
     context.Sp = pRegisterSet->SP;
     context.Pc = pRegisterSet->IP;
@@ -659,8 +669,11 @@ bool CoffNativeCodeManager::UnwindStackFrame(MethodInfo *    pMethodInfo,
 
     pRegisterSet->pIP = contextPointers.Lr;
 
-    for (int i = 8; i < 16; i++)
-        pRegisterSet->D[i - 8] = context.V[i].Low;
+    if (!(flags & USFF_GcUnwind))
+    {
+        for (int i = 8; i < 16; i++)
+            pRegisterSet->D[i - 8] = context.V[i].Low;
+    }
 #endif // defined(TARGET_X86)
 
     FOR_EACH_NONVOLATILE_REGISTER(CONTEXT_TO_REGDISPLAY);

diff --git a/src/coreclr/nativeaot/System.Private.CoreLib/src/System/RuntimeTypeHandle.cs b/src/coreclr/nativeaot/System.Private.CoreLib/src/System/RuntimeTypeHandle.cs
@@ -16,10 +16,7 @@ namespace System
     [StructLayout(LayoutKind.Sequential)]
     public unsafe struct RuntimeTypeHandle : IEquatable<RuntimeTypeHandle>, ISerializable
     {
-        //
-        // Caution: There can be and are multiple MethodTable for the "same" type (e.g. int[]). That means
-        // you can't use the raw IntPtr value for comparisons.
-        //
+        private IntPtr _value;
 
         internal RuntimeTypeHandle(EETypePtr pEEType)
             : this(pEEType.RawValue)
@@ -123,7 +120,5 @@ internal bool IsNull
                 return _value == new IntPtr(0);
             }
         }
-
-        private IntPtr _value;
     }
 }
diff --git a/src/coreclr/nativeaot/Test.CoreLib/src/System/RuntimeTypeHandle.cs b/src/coreclr/nativeaot/Test.CoreLib/src/System/RuntimeTypeHandle.cs
@@ -10,17 +10,17 @@ namespace System
     [StructLayout(LayoutKind.Sequential)]
     public struct RuntimeTypeHandle
     {
-        private EETypePtr _pEEType;
+        private IntPtr _value;
 
-        internal RuntimeTypeHandle(EETypePtr pEEType)
+        internal RuntimeTypeHandle(IntPtr value)
         {
-            _pEEType = pEEType;
+            _value = value;
         }
 
         [Intrinsic]
         internal static unsafe IntPtr ToIntPtr(RuntimeTypeHandle handle)
         {
-            return (IntPtr)handle._pEEType.ToPointer();
+            return handle._value;
         }
     }
 }
@@ -32,7 +32,7 @@ internal static class LdTokenHelpers
     {
         private static RuntimeTypeHandle GetRuntimeTypeHandle(IntPtr pEEType)
         {
-            return new RuntimeTypeHandle(new EETypePtr(pEEType));
+            return new RuntimeTypeHandle(pEEType);
         }
     }
 }