r351302 - [SEH] Pass the frame pointer from SEH finally to finally functions

[Sanjin Sijaric via cfe-commits]

Author: ssijaric
Date: Tue Jan 15 23:39:44 2019
New Revision: 351302

URL: http://llvm.org/viewvc/llvm-project?rev=351302&view=rev
Log:
[SEH] Pass the frame pointer from SEH finally to finally functions

Pass the frame pointer that the first finally block receives onto the nested
finally block, instead of generating it using localaddr.

Differential Revision: https://reviews.llvm.org/D56463

Added:
    cfe/trunk/test/CodeGen/exceptions-seh-nested-finally.c
Modified:
    cfe/trunk/lib/CodeGen/CGException.cpp

Modified: cfe/trunk/lib/CodeGen/CGException.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGException.cpp?rev=351302&r1=351301&r2=351302&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGException.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGException.cpp Tue Jan 15 23:39:44 2019
@@ -1627,8 +1627,16 @@ struct PerformSEHFinally final : EHScope
 
     // Compute the two argument values.
     QualType ArgTys[2] = {Context.UnsignedCharTy, Context.VoidPtrTy};
-    llvm::Value *LocalAddrFn = CGM.getIntrinsic(llvm::Intrinsic::localaddress);
-    llvm::Value *FP = CGF.Builder.CreateCall(LocalAddrFn);
+    llvm::Value *FP = nullptr;
+    // If CFG.IsOutlinedSEHHelper is true, then we are within a finally block.
+    if (CGF.IsOutlinedSEHHelper) {
+      FP = &CGF.CurFn->arg_begin()[1];
+    } else {
+      llvm::Value *LocalAddrFn =
+          CGM.getIntrinsic(llvm::Intrinsic::localaddress);
+      FP = CGF.Builder.CreateCall(LocalAddrFn);
+    }
+
     llvm::Value *IsForEH =
         llvm::ConstantInt::get(CGF.ConvertType(ArgTys[0]), F.isForEHCleanup());
     Args.add(RValue::get(IsForEH), ArgTys[0]);

Added: cfe/trunk/test/CodeGen/exceptions-seh-nested-finally.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/exceptions-seh-nested-finally.c?rev=351302&view=auto
==============================================================================
--- cfe/trunk/test/CodeGen/exceptions-seh-nested-finally.c (added)
+++ cfe/trunk/test/CodeGen/exceptions-seh-nested-finally.c Tue Jan 15 23:39:44 2019
@@ -0,0 +1,26 @@
+// RUN: %clang_cc1 %s -triple x86_64-pc-win32 -fms-extensions -emit-llvm -o - \
+// RUN:         | FileCheck %s
+// RUN: %clang_cc1 %s -triple i686-pc-win32 -fms-extensions -emit-llvm -o - \
+// RUN:         | FileCheck %s
+// RUN: %clang_cc1 %s -triple aarch64-windows -fms-extensions -emit-llvm -o - \
+// RUN:         | FileCheck %s
+
+// Check that the first finally block passes the enclosing function's frame
+// pointer to the second finally block, instead of generating it via localaddr.
+
+// CHECK-LABEL: define internal void @"?fin$0 at 0@main@@"({{i8( zeroext)?}} %abnormal_termination, i8* %frame_pointer)
+// CHECK: call void @"?fin$1 at 0@main@@"({{i8( zeroext)?}} 0, i8* %frame_pointer)
+int
+main() {
+  int Check = 0;
+  __try {
+    Check = 3;
+  } __finally {
+    __try {
+      Check += 2;
+    } __finally {
+      Check += 4;
+    }
+  }
+  return Check;
+}