Revert "Revert "ThinLTO: Verify bitcode before lauching the ThinLTOCodeGenerator.""

This reapplies commit r303438 modified to not verify cross-imported
bitcode in FunctionImporter.

rdar://problem/31233625

Differential Revision: https://reviews.llvm.org/D33370

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303470 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 96 insertions, 5 deletions

diff --git a/include/llvm/Transforms/IPO/FunctionImport.h b/include/llvm/Transforms/IPO/FunctionImport.h
index ed5742ab8b5..d66b6edc7a4 100644
--- a/include/llvm/Transforms/IPO/FunctionImport.h
+++ b/include/llvm/Transforms/IPO/FunctionImport.h
@@ -53,8 +53,7 @@ public:
       : Index(Index), ModuleLoader(std::move(ModuleLoader)) {}
 
   /// Import functions in Module \p M based on the supplied import list.
-  Expected<bool>
-  importFunctions(Module &M, const ImportMapTy &ImportList);
+  Expected<bool> importFunctions(Module &M, const ImportMapTy &ImportList);
 
 private:
   /// The summaries index used to trigger importing.
diff --git a/lib/LTO/ThinLTOCodeGenerator.cpp b/lib/LTO/ThinLTOCodeGenerator.cpp
index 327f2377d91..ca3fc60f950 100644
--- a/lib/LTO/ThinLTOCodeGenerator.cpp
+++ b/lib/LTO/ThinLTOCodeGenerator.cpp
@@ -25,9 +25,11 @@
 #include "llvm/Bitcode/BitcodeWriterPass.h"
 #include "llvm/ExecutionEngine/ObjectMemoryBuffer.h"
 #include "llvm/IR/DiagnosticPrinter.h"
+#include "llvm/IR/DebugInfo.h"
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/LegacyPassManager.h"
 #include "llvm/IR/Mangler.h"
+#include "llvm/IR/Verifier.h"
 #include "llvm/IRReader/IRReader.h"
 #include "llvm/LTO/LTO.h"
 #include "llvm/Linker/Linker.h"
@@ -62,6 +64,7 @@ namespace llvm {
 extern cl::opt<bool> LTODiscardValueNames;
 extern cl::opt<std::string> LTORemarksFilename;
 extern cl::opt<bool> LTOPassRemarksWithHotness;
+extern cl::opt<bool> LTOStripInvalidDebugInfo;
 }
 
 namespace {
@@ -142,6 +145,30 @@ static void promoteModule(Module &TheModule, const ModuleSummaryIndex &Index) {
     report_fatal_error("renameModuleForThinLTO failed");
 }
 
+namespace {
+class ThinLTODiagnosticInfo : public DiagnosticInfo {
+  const Twine &Msg;
+public:
+  ThinLTODiagnosticInfo(const Twine &DiagMsg,
+                        DiagnosticSeverity Severity = DS_Error)
+      : DiagnosticInfo(DK_Linker, Severity), Msg(DiagMsg) {}
+  void print(DiagnosticPrinter &DP) const override { DP << Msg; }
+};
+}
+
+/// Verify the module and strip broken debug info.
+static void verifyLoadedModule(Module &TheModule) {
+  bool BrokenDebugInfo = false;
+  if (verifyModule(TheModule, &dbgs(),
+                   LTOStripInvalidDebugInfo ? &BrokenDebugInfo : nullptr))
+    report_fatal_error("Broken module found, compilation aborted!");
+  if (BrokenDebugInfo) {
+    TheModule.getContext().diagnose(ThinLTODiagnosticInfo(
+        "Invalid debug info found, debug info will be stripped", DS_Warning));
+    StripDebugInfo(TheModule);
+  }
+}
+
 static std::unique_ptr<Module>
 loadModuleFromBuffer(const MemoryBufferRef &Buffer, LLVMContext &Context,
                      bool Lazy, bool IsImporting) {
@@ -159,6 +186,8 @@ loadModuleFromBuffer(const MemoryBufferRef &Buffer, LLVMContext &Context,
     });
     report_fatal_error("Can't load module, abort.");
   }
+  if (!Lazy)
+    verifyLoadedModule(*ModuleOrErr.get());
   return std::move(ModuleOrErr.get());
 }
 
@@ -181,6 +210,8 @@ crossImportIntoModule(Module &TheModule, const ModuleSummaryIndex &Index,
     });
     report_fatal_error("importFunctions failed");
   }
+  // Verify again after cross-importing.
+  verifyLoadedModule(TheModule);
 }
 
 static void optimizeModule(Module &TheModule, TargetMachine &TM,
@@ -195,7 +226,8 @@ static void optimizeModule(Module &TheModule, TargetMachine &TM,
   PMB.OptLevel = OptLevel;
   PMB.LoopVectorize = true;
   PMB.SLPVectorize = true;
-  PMB.VerifyInput = true;
+  // Already did this in verifyLoadedModule().
+  PMB.VerifyInput = false;
   PMB.VerifyOutput = false;
 
   legacy::PassManager PM;
diff --git a/test/LTO/X86/Inputs/strip-debug-info-bar.ll b/test/LTO/X86/Inputs/strip-debug-info-bar.ll
new file mode 100644
index 00000000000..4269886676b
--- /dev/null
+++ b/test/LTO/X86/Inputs/strip-debug-info-bar.ll
@@ -0,0 +1,15 @@
+target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-apple-macosx10.12"
+
+define void @bar() !dbg !3 {
+  ret void
+}
+
+!llvm.module.flags = !{!0}
+!llvm.dbg.cu = !{!1}
+
+!0 = !{i32 2, !"Debug Info Version", i32 3}
+!1 = distinct !DICompileUnit(language: DW_LANG_C99, file: !2)
+!2 = !DIFile(filename: "broken", directory: "")
+!3 = distinct !DISubprogram(line: 1000, isDefinition: true)
+
diff --git a/test/LTO/X86/Inputs/strip-debug-info.bc b/test/LTO/X86/Inputs/strip-debug-info.bc
deleted file mode 100644
index c83195ff9ca..00000000000
--- a/test/LTO/X86/Inputs/strip-debug-info.bc
+++ /dev/null
diff --git a/test/LTO/X86/strip-debug-info.ll b/test/LTO/X86/strip-debug-info.ll
index ff45ca15243..6b774516444 100644
--- a/test/LTO/X86/strip-debug-info.ll
+++ b/test/LTO/X86/strip-debug-info.ll
@@ -1,16 +1,61 @@
+; RUN: llvm-as -disable-verify %s -o %t.bc
+; ---- Full LTO ---------------------------------------------
 ; RUN: not llvm-lto -lto-strip-invalid-debug-info=false \
-; RUN:     -o %t.o %S/Inputs/strip-debug-info.bc 2>&1 | \
+; RUN:     -o %t.o %t.bc 2>&1 | \
 ; RUN:     FileCheck %s -allow-empty -check-prefix=CHECK-ERR
 ; RUN: llvm-lto -lto-strip-invalid-debug-info=true \
 ; RUN:     -exported-symbol foo -exported-symbol _foo \
-; RUN:     -o %t.o %S/Inputs/strip-debug-info.bc 2>&1 | \
+; RUN:     -o %t.o %t.bc 2>&1 | \
 ; RUN:     FileCheck %s -allow-empty -check-prefix=CHECK-WARN
 ; RUN: llvm-nm %t.o | FileCheck %s 
+; ---- Thin LTO (codegen only) ------------------------------
+; RUN: not llvm-lto -thinlto -thinlto-action=codegen \
+; RUN:     -lto-strip-invalid-debug-info=false \
+; RUN:     %t.bc -disable-verify 2>&1 | \
+; RUN:     FileCheck %s -allow-empty -check-prefix=CHECK-ERR
+; RUN: llvm-lto -thinlto -thinlto-action=codegen \
+; RUN:     -lto-strip-invalid-debug-info=true \
+; RUN:     %t.bc -disable-verify 2>&1 | \
+; RUN:     FileCheck %s -allow-empty -check-prefix=CHECK-WARN
+; ---- Thin LTO (optimize, strip main file) -----------------
+; RUN: opt -disable-verify -module-summary %s -o %t.bc
+; RUN: opt -disable-verify -module-summary %S/Inputs/strip-debug-info-bar.ll \
+; RUN:     -o %t2.bc
+; RUN: not llvm-lto -thinlto -thinlto-action=run \
+; RUN:     -lto-strip-invalid-debug-info=false \
+; RUN:     %t.bc -disable-verify 2>&1 | \
+; RUN:     FileCheck %s -allow-empty -check-prefix=CHECK-ERR
+; RUN: llvm-lto -thinlto -thinlto-action=run \
+; RUN:     -lto-strip-invalid-debug-info=true \
+; RUN:     %t.bc -disable-verify 2>&1 | \
+; RUN:     FileCheck %s -allow-empty -check-prefix=CHECK-WARN
+; ---- Thin LTO (optimize, strip imported file) -------------
+; RUN: opt -disable-verify -strip-debug -module-summary %t.bc -o %t-stripped.bc
+; RUN: llvm-lto -thinlto-action=thinlink -o %t.index.bc %t-stripped.bc %t2.bc
+; RUN: not llvm-lto -thinlto -thinlto-action=import \
+; RUN:     -thinlto-index=%t.index.bc \
+; RUN:     -lto-strip-invalid-debug-info=false \
+; RUN:     -exported-symbol foo -exported-symbol _foo \
+; RUN:     %t-stripped.bc -disable-verify 2>&1 | \
+; RUN:     FileCheck %s -allow-empty -check-prefix=CHECK-ERR
+; RUN: llvm-lto -thinlto -thinlto-action=import \
+; RUN:     -lto-strip-invalid-debug-info=true \
+; RUN:     -thinlto-index=%t.index.bc \
+; RUN:     -exported-symbol foo -exported-symbol _foo \
+; RUN:     %t-stripped.bc -disable-verify 2>&1 | \
+; RUN:     FileCheck %s -allow-empty -check-prefix=CHECK-WARN
 
 ; CHECK-ERR: Broken module found, compilation aborted
 ; CHECK-WARN: Invalid debug info found, debug info will be stripped
+; CHECK-WARN-NOT: Broken module found
 ; CHECK: foo
+target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-apple-macosx10.12"
+
+declare void @bar()
+
 define void @foo() {
+  call void @bar()
   ret void
 }