Resolve one integration test failure

Also tolerate blank lines and trim whitespace in patch function files.

Author: sivadeilra

clang/lib/CodeGen/CodeGenModule.cpp

@@ -464,7 +464,10 @@ CodeGenModule::CodeGenModule(ASTContext &C,
         const llvm::MemoryBuffer &FileBuffer = **BufOrErr;
         for (llvm::line_iterator I(FileBuffer.getMemBufferRef(), true), E;
              I != E; ++I) {
-          this->MSHotPatchFunctions.push_back(std::string{*I});
+          llvm::StringRef Line = llvm::StringRef(*I).trim();
+          if (!Line.empty()) {
+            this->MSHotPatchFunctions.push_back(std::string{Line});
+          }
         }
       } else {
         auto &DE = Context.getDiagnostics();

clang/test/CodeGen/ms-hotpatch-file.c

@@ -0,0 +1,21 @@
+// This verifies that hotpatch function attributes are correctly propagated when compiling directly to OBJ.
+//
+// RUN: echo this_gets_hotpatched > %t-hotpatch-functions.txt
+// RUN: %clang_cl -c --target=x86_64-windows-msvc -O2 /Z7 -fms-hotpatch-functions-file=%t-hotpatch-functions.txt /Fo%t.obj %s
+// RUN: llvm-readobj --codeview %t.obj | FileCheck %s
+
+void this_might_have_side_effects();
+
+int __declspec(noinline) this_gets_hotpatched() {
+    this_might_have_side_effects();
+    return 42;
+}
+
+// CHECK: Kind: S_HOTPATCHFUNC (0x1169)
+// CHECK-NEXT: Function: this_gets_hotpatched
+
+int __declspec(noinline) this_does_not_get_hotpatched() {
+    return this_gets_hotpatched() + 100;
+}
+
+// CHECK-NOT: S_HOTPATCHFUNC

clang/test/CodeGen/ms-hotpatch-functions.txt

@@ -1,13 +1,14 @@
 // This verifies that hotpatch function attributes are correctly propagated through LLVM IR when compiling with LTO.
 //
-// RUN: %clang_cl -c --target=x86_64-windows-msvc -O2 /Z7 -fms-hotpatch-functions-file=%S/ms-hotpatch-functions.txt -flto /Fo%t.bc %s
+// RUN: echo this_gets_hotpatched > %t-hotpatch-functions.txt
+// RUN: %clang_cl -c --target=x86_64-windows-msvc -O2 /Z7 -fms-hotpatch-functions-file=%t-hotpatch-functions.txt -flto /Fo%t.bc %s
 // RUN: llvm-dis %t.bc -o - | FileCheck %s
 //
 // CHECK: ; Function Attrs: marked_for_windows_hot_patching mustprogress nofree noinline norecurse nosync nounwind sspstrong willreturn memory(none) uwtable
-// CHECK-NEXT: define dso_local noundef i32 @this_gets_hotpatched() local_unnamed_addr #0 !dbg !13 {
+// CHECK-NEXT: define dso_local noundef i32 @this_gets_hotpatched()
 //
 // CHECK: ; Function Attrs: mustprogress nofree noinline norecurse nosync nounwind sspstrong willreturn memory(none) uwtable
-// CHECK-NEXT: define dso_local noundef i32 @this_does_not_get_hotpatched() local_unnamed_addr #1 !dbg !19 {
+// CHECK-NEXT: define dso_local noundef i32 @this_does_not_get_hotpatched()
 
 int __declspec(noinline) this_gets_hotpatched() {
     return 42;

clang/test/CodeGen/ms-hotpatch-lto.c

@@ -1,6 +1,6 @@
 // This verifies that hotpatch function attributes are correctly propagated when compiling directly to OBJ.
 //
-// RUN: %clang_cl -c --target=x86_64-windows-msvc -O2 /Z7 -fms-hotpatch-functions-file=%S/ms-hotpatch-functions.txt /Fo%t.obj %s
+// RUN: %clang_cl -c --target=x86_64-windows-msvc -O2 /Z7 -fms-hotpatch-functions-list=this_gets_hotpatched /Fo%t.obj %s
 // RUN: llvm-readobj --codeview %t.obj | FileCheck %s
 
 void this_might_have_side_effects();

clang/test/CodeGen/ms-hotpatch.c

@@ -98,7 +98,10 @@ bool WindowsHotPatch::runOnModule(Module &M) {
         const llvm::MemoryBuffer &FileBuffer = **BufOrErr;
         for (llvm::line_iterator I(FileBuffer.getMemBufferRef(), true), E;
              I != E; ++I) {
-          HotPatchFunctionsList.push_back(std::string{*I});
+          auto Line = llvm::StringRef(*I).trim();
+          if (!Line.empty()) {
+            HotPatchFunctionsList.push_back(std::string{Line});
+          }
         }
       } else {
         M.getContext().diagnose(llvm::DiagnosticInfoGeneric{