[CodeView] Mark our lines as statements, not expressions

The line tables for CodeView make a distinction between expressions and
statements.  As it turns out, MSVC always emits them as statements and
we always emit them as expressions.  Let's switch to statements to match
the CodeView that they emit.

llvm-svn: 257553

1 files changed, 18 insertions, 3 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/WinCodeViewLineTables.cpp b/llvm/lib/CodeGen/AsmPrinter/WinCodeViewLineTables.cpp
index 52116ce1e22..1e2f55b7115 100644
--- a/llvm/lib/CodeGen/AsmPrinter/WinCodeViewLineTables.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/WinCodeViewLineTables.cpp
@@ -82,13 +82,24 @@ void WinCodeViewLineTables::maybeRecordLocation(DebugLoc DL,
   const MDNode *Scope = DL.getScope();
   if (!Scope)
     return;
+  unsigned LineNumber = DL.getLine();
+  // Skip this line if it is longer than the maximum we can record.
+  if (LineNumber > COFF::CVL_MaxLineNumber)
+    return;
+
+  unsigned ColumnNumber = DL.getCol();
+  // Truncate the column number if it is longer than the maximum we can record.
+  if (ColumnNumber > COFF::CVL_MaxColumnNumber)
+    ColumnNumber = 0;
+
   StringRef Filename = getFullFilepath(Scope);
 
   // Skip this instruction if it has the same file:line as the previous one.
   assert(CurFn);
   if (!CurFn->Instrs.empty()) {
     const InstrInfoTy &LastInstr = InstrInfo[CurFn->Instrs.back()];
-    if (LastInstr.Filename == Filename && LastInstr.LineNumber == DL.getLine())
+    if (LastInstr.Filename == Filename && LastInstr.LineNumber == LineNumber &&
+        LastInstr.ColumnNumber == ColumnNumber)
       return;
   }
   FileNameRegistry.add(Filename);
@@ -96,7 +107,7 @@ void WinCodeViewLineTables::maybeRecordLocation(DebugLoc DL,
   MCSymbol *MCL = Asm->MMI->getContext().createTempSymbol();
   Asm->OutStreamer->EmitLabel(MCL);
   CurFn->Instrs.push_back(MCL);
-  InstrInfo[MCL] = InstrInfoTy(Filename, DL.getLine(), DL.getCol());
+  InstrInfo[MCL] = InstrInfoTy(Filename, LineNumber, ColumnNumber);
 }
 
 WinCodeViewLineTables::WinCodeViewLineTables(AsmPrinter *AP)
@@ -282,6 +293,7 @@ void WinCodeViewLineTables::emitDebugInfoForFunction(const Function *GV) {
                 ColSegEnd = ColSegI + FilenameSegmentLengths[LastSegmentStart];
          ColSegI != ColSegEnd; ++ColSegI) {
       unsigned ColumnNumber = InstrInfo[FI.Instrs[ColSegI]].ColumnNumber;
+      assert(ColumnNumber <= COFF::CVL_MaxColumnNumber);
       Asm->EmitInt16(ColumnNumber); // Start column
       Asm->EmitInt16(0);            // End column
     }
@@ -320,7 +332,10 @@ void WinCodeViewLineTables::emitDebugInfoForFunction(const Function *GV) {
 
     // The first PC with the given linenumber and the linenumber itself.
     EmitLabelDiff(*Asm->OutStreamer, Fn, Instr);
-    Asm->EmitInt32(InstrInfo[Instr].LineNumber);
+    uint32_t LineNumber = InstrInfo[Instr].LineNumber;
+    assert(LineNumber <= COFF::CVL_MaxLineNumber);
+    uint32_t LineData = LineNumber | COFF::CVL_IsStatement;
+    Asm->EmitInt32(LineData);
   }
 
   FinishPreviousChunk();