From 2cf9e9dc983423232c7eba1b1595dec5f5d522cc Mon Sep 17 00:00:00 2001
From: bruteforceboy <ogbonnachibuoyim12@gmail.com>
Date: Tue, 4 Mar 2025 12:01:47 +0300
Subject: [PATCH] [CIR][CodeGen] Fix std::ofstream fail during CodeGen

---
 clang/lib/CIR/CodeGen/CIRGenFunction.cpp |  4 ++
 clang/test/CIR/CodeGen/ofstream.cpp      | 87 ++++++++++++++++++++++++
 2 files changed, 91 insertions(+)
 create mode 100644 clang/test/CIR/CodeGen/ofstream.cpp

diff --git a/clang/lib/CIR/CodeGen/CIRGenFunction.cpp b/clang/lib/CIR/CodeGen/CIRGenFunction.cpp
index 39ea3f0fbf20..c2a91bda8215 100644
--- a/clang/lib/CIR/CodeGen/CIRGenFunction.cpp
+++ b/clang/lib/CIR/CodeGen/CIRGenFunction.cpp
@@ -388,6 +388,10 @@ void CIRGenFunction::LexicalScope::cleanup() {
     }
 
     if (localScope->Depth == 0) {
+      mlir::Block *currBlock = builder.getInsertionBlock();
+      if (currBlock->mightHaveTerminator())
+        currBlock->getTerminator()->erase();
+
       // TODO(cir): get rid of all this special cases once cleanups are properly
       // implemented.
       // TODO(cir): most of this code should move into emitBranchThroughCleanup
diff --git a/clang/test/CIR/CodeGen/ofstream.cpp b/clang/test/CIR/CodeGen/ofstream.cpp
new file mode 100644
index 000000000000..bd7978fe2b81
--- /dev/null
+++ b/clang/test/CIR/CodeGen/ofstream.cpp
@@ -0,0 +1,87 @@
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -fcxx-exceptions -fexceptions -I%S/../Inputs -fclangir -emit-cir %s -o %t.cir
+// RUN: FileCheck --check-prefix=CIR --input-file=%t.cir %s
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -fcxx-exceptions -fexceptions -I%S/../Inputs -fclangir -emit-llvm %s -o %t.ll
+// RUN: FileCheck --check-prefix=LLVM --input-file=%t.ll %s
+
+#include "std-cxx.h"
+
+namespace std {
+template <class CharT> class basic_ofstream {
+public:
+  basic_ofstream();
+  ~basic_ofstream();
+  explicit basic_ofstream(const char *);
+};
+
+using ofstream = basic_ofstream<char>;
+
+ofstream &operator<<(ofstream &, const string &);
+} // namespace std
+
+void foo(const char *path) {
+  std::ofstream fout1(path);
+  fout1 << path;
+  std::ofstream fout2(path);
+  fout2 << path;
+}
+
+// CIR: cir.func @_Z3fooPKc
+// CIR: %[[V1:.*]] = cir.alloca !ty_std3A3Abasic_ofstream3Cchar3E, !cir.ptr<!ty_std3A3Abasic_ofstream3Cchar3E>, ["fout1", init] {alignment = 1 : i64}
+// CIR: %[[V2:.*]] = cir.alloca !ty_std3A3Abasic_ofstream3Cchar3E, !cir.ptr<!ty_std3A3Abasic_ofstream3Cchar3E>, ["fout2", init] {alignment = 1 : i64}
+// CIR: cir.try synthetic cleanup {
+// CIR:   cir.call exception @_ZNSbIcEC1EPKcRKNS_9AllocatorE({{.*}}, {{.*}}, {{.*}}) : (!cir.ptr<!ty_std3A3Abasic_string3Cchar3E>, !cir.ptr<!s8i>, !cir.ptr<!ty_std3A3Abasic_string3Cchar3E3A3AAllocator>) -> () cleanup {
+// CIR:     cir.call @_ZNSt14basic_ofstreamIcED1Ev(%[[V2]]) : (!cir.ptr<!ty_std3A3Abasic_ofstream3Cchar3E>) -> ()
+// CIR:     cir.call @_ZNSt14basic_ofstreamIcED1Ev(%[[V1]]) : (!cir.ptr<!ty_std3A3Abasic_ofstream3Cchar3E>) -> ()
+// CIR:     cir.yield
+// CIR:   }
+// CIR:   cir.yield
+// CIR: } catch [#cir.unwind {
+// CIR:   cir.resume
+// CIR: }]
+// CIR: cir.try synthetic cleanup {
+// CIR:   %[[V10:.*]] = cir.call exception @_ZStlsRSt14basic_ofstreamIcERKSbIcE(%[[V2]], {{.*}}) : (!cir.ptr<!ty_std3A3Abasic_ofstream3Cchar3E>, !cir.ptr<!ty_std3A3Abasic_string3Cchar3E>) -> !cir.ptr<!ty_std3A3Abasic_ofstream3Cchar3E> cleanup {
+// CIR:     cir.call @_ZNSbIcED1Ev({{.*}}) : (!cir.ptr<!ty_std3A3Abasic_string3Cchar3E>) -> ()
+// CIR:     cir.call @_ZNSt14basic_ofstreamIcED1Ev(%[[V2]]) : (!cir.ptr<!ty_std3A3Abasic_ofstream3Cchar3E>) -> ()
+// CIR:     cir.call @_ZNSt14basic_ofstreamIcED1Ev(%[[V1]]) : (!cir.ptr<!ty_std3A3Abasic_ofstream3Cchar3E>) -> ()
+// CIR:     cir.yield
+// CIR:   }
+// CIR:   cir.store %[[V10]], {{.*}} : !cir.ptr<!ty_std3A3Abasic_ofstream3Cchar3E>, !cir.ptr<!cir.ptr<!ty_std3A3Abasic_ofstream3Cchar3E>>
+// CIR:   cir.yield
+// CIR: } catch [#cir.unwind {
+// CIR:   cir.resume
+// CIR: }]
+// CIR: cir.call @_ZNSt14basic_ofstreamIcED1Ev(%[[V2]]) : (!cir.ptr<!ty_std3A3Abasic_ofstream3Cchar3E>) -> ()
+// CIR: cir.call @_ZNSt14basic_ofstreamIcED1Ev(%[[V1]]) : (!cir.ptr<!ty_std3A3Abasic_ofstream3Cchar3E>) -> ()
+// CIR: cir.return
+
+// LLVM: @_Z3fooPKc(ptr {{.*}})
+// LLVM:   %[[V9:.*]] = alloca %"class.std::basic_ofstream<char>", i64 1, align 1
+// LLVM:   %[[V10:.*]] = alloca %"class.std::basic_ofstream<char>", i64 1, align 1
+// LLVM: {{.*}}
+// LLVM:   invoke void @_ZNSbIcEC1EPKcRKNS_9AllocatorE(ptr {{.*}}, ptr {{.*}}, ptr {{.*}})
+// LLVM:           to label %[[B56:.*]] unwind label %[[B57:.*]]
+// LLVM: [[B56]]
+// LLVM:   br label {{.*}}
+// LLVM: [[B57]]
+// LLVM:   call void @_ZNSt14basic_ofstreamIcED1Ev(ptr %[[V10]])
+// LLVM:   call void @_ZNSt14basic_ofstreamIcED1Ev(ptr %[[V9]])
+// LLVM:   br label %[[B61:.*]]
+// LLVM: [[B61]]
+// LLVM:   resume { ptr, i32 } {{.*}}
+// LLVM: {{.*}}
+// LLVM:   {{.*}} = invoke ptr @_ZStlsRSt14basic_ofstreamIcERKSbIcE(ptr %[[V10]], ptr {{.*}})
+// LLVM:           to label {{.*}} unwind label %[[B70:.*]]
+// LLVM: [[B70]]
+// LLVM:   call void @_ZNSbIcED1Ev(ptr {{.*}})
+// LLVM:   call void @_ZNSt14basic_ofstreamIcED1Ev(ptr %[[V10]])
+// LLVM:   call void @_ZNSt14basic_ofstreamIcED1Ev(ptr %[[V9]])
+// LLVM:   br label %[[B74:.*]]
+// LLVM: [[B74]]
+// LLVM:   resume { ptr, i32 } {{.*}}
+// LLVM: {{.*}}
+// LLVM:   call void @_ZNSbIcED1Ev(ptr {{.*}})
+// LLVM:   br label %[[B80:.*]]
+// LLVM: [[B80]]
+// LLVM:   call void @_ZNSt14basic_ofstreamIcED1Ev(ptr %[[V10]])
+// LLVM:   call void @_ZNSt14basic_ofstreamIcED1Ev(ptr %[[V9]])
+// LLVM:   ret void