LTO: Ignore disabled diagnostic remarks

r206400 and r209442 added remarks that are disabled by default.
However, if a diagnostic handler is registered, the remarks are sent
unfiltered to the handler.  This is the right behaviour for clang, since
it has its own filters.

However, the diagnostic handler exposed in the LTO API receives only the
severity and message.  It doesn't have the information to filter by pass
name.  For LTO, disabled remarks should be filtered by the producer.

I've changed `LLVMContext::setDiagnosticHandler()` to take a `bool`
argument indicating whether to respect the built-in filters.  This
defaults to `false`, so other consumers don't have a behaviour change,
but `LTOCodeGenerator::setDiagnosticHandler()` sets it to `true`.

To make this behaviour testable, I added a `-use-diagnostic-handler`
command-line option to `llvm-lto`.

This fixes PR21108.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218784 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/IR/LLVMContext.h b/include/llvm/IR/LLVMContext.h
index 2914caaf51cca15792f51a07a1eb9d8beec54f6b..cdd2150153fa77a0fae8d04c5b20fed8bbbe9b76 100644 (file)
--- a/include/llvm/IR/LLVMContext.h
+++ b/include/llvm/IR/LLVMContext.h
@@ -99,12 +99,14 @@ public:
   /// setDiagnosticHandler - This method sets a handler that is invoked
   /// when the backend needs to report anything to the user.  The first
   /// argument is a function pointer and the second is a context pointer that
-  /// gets passed into the DiagHandler.
+  /// gets passed into the DiagHandler.  The third argument should be set to
+  /// true if the handler only expects enabled diagnostics.
   ///
   /// LLVMContext doesn't take ownership or interpret either of these
   /// pointers.
   void setDiagnosticHandler(DiagnosticHandlerTy DiagHandler,
-                            void *DiagContext = nullptr);
+                            void *DiagContext = nullptr,
+                            bool RespectFilters = false);
 
   /// getDiagnosticHandler - Return the diagnostic handler set by
   /// setDiagnosticHandler.

diff --git a/lib/IR/LLVMContext.cpp b/lib/IR/LLVMContext.cpp
index d4ba83dfa622c1483fd2f92dcb824c9e88b0e38f..73ddc8cbe20cda39c0bca7a360883613c1ec6feb 100644 (file)
--- a/lib/IR/LLVMContext.cpp
+++ b/lib/IR/LLVMContext.cpp
@@ -112,9 +112,11 @@ void *LLVMContext::getInlineAsmDiagnosticContext() const {
 }
 
 void LLVMContext::setDiagnosticHandler(DiagnosticHandlerTy DiagnosticHandler,
-                                       void *DiagnosticContext) {
+                                       void *DiagnosticContext,
+                                       bool RespectFilters) {
   pImpl->DiagnosticHandler = DiagnosticHandler;
   pImpl->DiagnosticContext = DiagnosticContext;
+  pImpl->RespectDiagnosticFilters = RespectFilters;
 }
 
 LLVMContext::DiagnosticHandlerTy LLVMContext::getDiagnosticHandler() const {
@@ -145,13 +147,7 @@ void LLVMContext::emitError(const Instruction *I, const Twine &ErrorStr) {
   diagnose(DiagnosticInfoInlineAsm(*I, ErrorStr));
 }
 
-void LLVMContext::diagnose(const DiagnosticInfo &DI) {
-  // If there is a report handler, use it.
-  if (pImpl->DiagnosticHandler) {
-    pImpl->DiagnosticHandler(DI, pImpl->DiagnosticContext);
-    return;
-  }
-
+static bool isDiagnosticEnabled(const DiagnosticInfo &DI) {
   // Optimization remarks are selective. They need to check whether the regexp
   // pattern, passed via one of the -pass-remarks* flags, matches the name of
   // the pass that is emitting the diagnostic. If there is no match, ignore the
@@ -159,19 +155,32 @@ void LLVMContext::diagnose(const DiagnosticInfo &DI) {
   switch (DI.getKind()) {
   case llvm::DK_OptimizationRemark:
     if (!cast<DiagnosticInfoOptimizationRemark>(DI).isEnabled())
-      return;
+      return false;
     break;
   case llvm::DK_OptimizationRemarkMissed:
     if (!cast<DiagnosticInfoOptimizationRemarkMissed>(DI).isEnabled())
-      return;
+      return false;
     break;
   case llvm::DK_OptimizationRemarkAnalysis:
     if (!cast<DiagnosticInfoOptimizationRemarkAnalysis>(DI).isEnabled())
-      return;
+      return false;
     break;
   default:
     break;
   }
+  return true;
+}
+
+void LLVMContext::diagnose(const DiagnosticInfo &DI) {
+  // If there is a report handler, use it.
+  if (pImpl->DiagnosticHandler) {
+    if (!pImpl->RespectDiagnosticFilters || isDiagnosticEnabled(DI))
+      pImpl->DiagnosticHandler(DI, pImpl->DiagnosticContext);
+    return;
+  }
+
+  if (!isDiagnosticEnabled(DI))
+    return;
 
   // Otherwise, print the message with a prefix based on the severity.
   std::string MsgStorage;

diff --git a/lib/IR/LLVMContextImpl.cpp b/lib/IR/LLVMContextImpl.cpp
index 6513965ae7ad88da2eead12b348685b98a3f4bc4..09bf6b123a909115c16b15002ec1968cd885b0d8 100644 (file)
--- a/lib/IR/LLVMContextImpl.cpp
+++ b/lib/IR/LLVMContextImpl.cpp
@@ -40,6 +40,7 @@ LLVMContextImpl::LLVMContextImpl(LLVMContext &C)
   InlineAsmDiagContext = nullptr;
   DiagnosticHandler = nullptr;
   DiagnosticContext = nullptr;
+  RespectDiagnosticFilters = false;
   YieldCallback = nullptr;
   YieldOpaqueHandle = nullptr;
   NamedStructTypesUniqueID = 0;

diff --git a/lib/IR/LLVMContextImpl.h b/lib/IR/LLVMContextImpl.h
index b376064d2ed3b7de38eee21895ec42f1efbd5571..bd0097c31ba9b9a680a5ab5b1277fa71b5dbbc95 100644 (file)
--- a/lib/IR/LLVMContextImpl.h
+++ b/lib/IR/LLVMContextImpl.h
@@ -244,6 +244,7 @@ public:
 
   LLVMContext::DiagnosticHandlerTy DiagnosticHandler;
   void *DiagnosticContext;
+  bool RespectDiagnosticFilters;
 
   LLVMContext::YieldCallbackTy YieldCallback;
   void *YieldOpaqueHandle;

diff --git a/lib/LTO/LTOCodeGenerator.cpp b/lib/LTO/LTOCodeGenerator.cpp
index 1b6f905f0aca1df802cda3c4a82f679516516618..75ca56fbbe7333da15044b4dfc79f460948ea94e 100644 (file)
--- a/lib/LTO/LTOCodeGenerator.cpp
+++ b/lib/LTO/LTOCodeGenerator.cpp
@@ -558,5 +558,5 @@ LTOCodeGenerator::setDiagnosticHandler(lto_diagnostic_handler_t DiagHandler,
     return Context.setDiagnosticHandler(nullptr, nullptr);
   // Register the LTOCodeGenerator stub in the LLVMContext to forward the
   // diagnostic to the external DiagHandler.
-  Context.setDiagnosticHandler(LTOCodeGenerator::DiagnosticHandler, this);
+  Context.setDiagnosticHandler(LTOCodeGenerator::DiagnosticHandler, this, true);
 }

diff --git a/test/LTO/diagnostic-handler-remarks.ll b/test/LTO/diagnostic-handler-remarks.ll
new file mode 100644 (file)
index 0000000..bc3ce25
--- /dev/null
+++ b/test/LTO/diagnostic-handler-remarks.ll
@@ -0,0 +1,38 @@
+; RUN: llvm-as < %s >%t.bc
+; PR21108: Diagnostic handlers get pass remarks, even if they're not enabled.
+
+; Confirm that there are -pass-remarks.
+; RUN: llvm-lto -pass-remarks=inline \
+; RUN:          -exported-symbol _main -o %t.o %t.bc 2>&1 | \
+; RUN:     FileCheck %s -allow-empty -check-prefix=REMARKS
+; RUN: llvm-nm %t.o | FileCheck %s -check-prefix NM
+
+; RUN: llvm-lto -pass-remarks=inline -use-diagnostic-handler \
+; RUN:         -exported-symbol _main -o %t.o %t.bc 2>&1 | \
+; RUN:     FileCheck %s -allow-empty -check-prefix=REMARKS
+; RUN: llvm-nm %t.o | FileCheck %s -check-prefix NM
+
+; Confirm that -pass-remarks are not printed by default.
+; RUN: llvm-lto \
+; RUN:         -exported-symbol _main -o %t.o %t.bc 2>&1 | \
+; RUN:     FileCheck %s -allow-empty
+; RUN: llvm-nm %t.o | FileCheck %s -check-prefix NM
+
+; RUN: llvm-lto -use-diagnostic-handler \
+; RUN:         -exported-symbol _main -o %t.o %t.bc 2>&1 | \
+; RUN:     FileCheck %s -allow-empty
+; RUN: llvm-nm %t.o | FileCheck %s -check-prefix NM
+
+; REMARKS: remark:
+; CHECK-NOT: remark:
+; NM-NOT: foo
+; NM: main
+
+define i32 @foo() {
+  ret i32 7
+}
+
+define i32 @main() {
+  %i = call i32 @foo()
+  ret i32 %i
+}

diff --git a/tools/llvm-lto/llvm-lto.cpp b/tools/llvm-lto/llvm-lto.cpp
index 2f19090dfc9384ac2d947eed66cb9f7915aa6577..2bfd9594555dc6b58483f20d33305f393aad9e2e 100644 (file)
--- a/tools/llvm-lto/llvm-lto.cpp
+++ b/tools/llvm-lto/llvm-lto.cpp
@@ -38,6 +38,10 @@ static cl::opt<bool>
 DisableGVNLoadPRE("disable-gvn-loadpre", cl::init(false),
   cl::desc("Do not run the GVN load PRE pass"));
 
+static cl::opt<bool>
+UseDiagnosticHandler("use-diagnostic-handler", cl::init(false),
+  cl::desc("Use a diagnostic handler to test the handler interface"));
+
 static cl::list<std::string>
 InputFilenames(cl::Positional, cl::OneOrMore,
   cl::desc("<input bitcode files>"));
@@ -63,6 +67,25 @@ struct ModuleInfo {
 };
 }
 
+void handleDiagnostics(lto_codegen_diagnostic_severity_t Severity,
+                       const char *Msg, void *) {
+  switch (Severity) {
+  case LTO_DS_NOTE:
+    errs() << "note: ";
+    break;
+  case LTO_DS_REMARK:
+    errs() << "remark: ";
+    break;
+  case LTO_DS_ERROR:
+    errs() << "error: ";
+    break;
+  case LTO_DS_WARNING:
+    errs() << "warning: ";
+    break;
+  }
+  errs() << Msg << "\n";
+}
+
 int main(int argc, char **argv) {
   // Print a stack trace if we signal out.
   sys::PrintStackTraceOnErrorSignal();
@@ -84,6 +107,9 @@ int main(int argc, char **argv) {
 
   LTOCodeGenerator CodeGen;
 
+  if (UseDiagnosticHandler)
+    CodeGen.setDiagnosticHandler(handleDiagnostics, nullptr);
+
   switch (RelocModel) {
   case Reloc::Static:
     CodeGen.setCodePICModel(LTO_CODEGEN_PIC_MODEL_STATIC);