Fixed some debug locations with line 0 (#3784)

include/llvm/IR/IRBuilder.h

@@ -106,7 +106,13 @@ public:
   }
 
   /// \brief Set location information used by debugging information.
-  void SetCurrentDebugLocation(DebugLoc L) { CurDbgLocation = std::move(L); }
+  void SetCurrentDebugLocation(DebugLoc L) { CurDbgLocation = std::move(L);
+    // HLSL Change - begin
+    // Don't propagate debug locations at line 0
+    if (CurDbgLocation && CurDbgLocation.getLine() == 0)
+      CurDbgLocation = nullptr;
+    // HLSL Change - end
+  }
 
   /// \brief Get location information used by debugging information.
   const DebugLoc &getCurrentDebugLocation() const { return CurDbgLocation; }

lib/Transforms/Scalar/ScalarReplAggregatesHLSL.cpp

@@ -6087,7 +6087,7 @@ void PatchDebugInfo(DebugInfoFinder &DbgFinder, Function *F, GlobalVariable *GV,
   DITypeIdentifierMap EmptyMap;
   DIBuilder DIB(*GV->getParent());
   DIScope *Scope = Subprogram;
-  DebugLoc Loc = DebugLoc::get(0, 0, Scope);
+  DebugLoc Loc = DebugLoc::get(DGV->getLine(), 0, Scope);
 
   // If the variable is a member of another variable, find the offset and size
   bool IsFragment = false;

lib/Transforms/Utils/InlineFunction.cpp

@@ -885,7 +885,8 @@ static void fixupLineNumbers(Function *Fn, Function::iterator FI,
     if (!getDebugMetadataVersionFromModule(*Fn->getParent()))
       return;
     if (DISubprogram *Subprogram = getDISubprogram(Fn)) {
-      TheCallDL = DebugLoc(llvm::DILocation::get(Fn->getContext(), 0, 0, Subprogram));
+      // Just give it the submodule's line, so it doesn't have line number 0
+      TheCallDL = DebugLoc(llvm::DILocation::get(Fn->getContext(), Subprogram->getLine(), 0, Subprogram));
       TheCall->setDebugLoc(TheCallDL);
     }
     else {

tools/clang/test/HLSLFileCheck/dxil/debug/line_0.hlsl

@@ -0,0 +1,28 @@
+// RUN: %dxc -Zi -E main -T ps_6_0 /Zi /O0 %s | FileCheck %s
+
+// CHECK-NOT: !{{[0-9]+}} = !DILocation(line: 0,
+
+// Regression test to make sure debug locations with 0
+// as line number don't show up.
+
+struct My_Struct {
+  float m_foo;
+  float m_bar;
+  void set_foo(float foo) {
+    m_foo = foo;
+    m_foo *= 2;
+  }
+  void test() {
+    m_bar = m_bar * 2;
+  }
+};
+
+static My_Struct s = { 0.0, 0.0 };
+
+[RootSignature("")]
+float main(float foo : FOO) : SV_Target {
+  s.set_foo(foo);
+  s.test();
+  return s.m_bar;
+}
+