Merge pull request #14421 from eeckstein/fix-nd-4.1

[4.1] Fix two issues which prevents incremental llvm compilation

Author: eeckstein

lib/Frontend/CompilerInvocation.cpp

@@ -1252,10 +1252,17 @@ static bool ParseDiagnosticArgs(DiagnosticOptions &Opts, ArgList &Args,
 }
 
 // Lifted from the clang driver.
-static void PrintArg(raw_ostream &OS, const char *Arg, bool Quote) {
+static void PrintArg(raw_ostream &OS, const char *Arg, StringRef TempDir) {
   const bool Escape = std::strpbrk(Arg, "\"\\$ ");
 
-  if (!Quote && !Escape) {
+  if (StringRef(Arg).startswith(TempDir)) {
+    // Don't write temporary file names in the debug info. This would prevent
+    // incremental llvm compilation because we would generate different IR on
+    // every compiler invocation.
+    Arg = "<temporary-file>";
+  }
+
+  if (!Escape) {
     OS << Arg;
     return;
   }
@@ -1479,9 +1486,14 @@ void CompilerInvocation::buildDWARFDebugFlags(std::string &Output,
                                               const ArrayRef<const char*> &Args,
                                               StringRef SDKPath,
                                               StringRef ResourceDir) {
+  // This isn't guaranteed to be the same temp directory as what the driver
+  // uses, but it's highly likely.
+  llvm::SmallString<128> TDir;
+  llvm::sys::path::system_temp_directory(true, TDir);
+
   llvm::raw_string_ostream OS(Output);
   interleave(Args,
-             [&](const char *Argument) { PrintArg(OS, Argument, false); },
+             [&](const char *Argument) { PrintArg(OS, Argument, TDir.str()); },
              [&] { OS << " "; });
 
   // Inject the SDK path and resource dir if they are nonempty and missing.
@@ -1497,11 +1509,11 @@ void CompilerInvocation::buildDWARFDebugFlags(std::string &Output,
   }
   if (!haveSDKPath) {
     OS << " -sdk ";
-    PrintArg(OS, SDKPath.data(), false);
+    PrintArg(OS, SDKPath.data(), TDir.str());
   }
   if (!haveResourceDir) {
     OS << " -resource-dir ";
-    PrintArg(OS, ResourceDir.data(), false);
+    PrintArg(OS, ResourceDir.data(), TDir.str());
   }
 }
 

lib/SILOptimizer/SILCombiner/SILCombinerMiscVisitors.cpp

@@ -477,11 +477,18 @@ SILInstruction *SILCombiner::visitLoadInst(LoadInst *LI) {
   // Given a load with multiple struct_extracts/tuple_extracts and no other
   // uses, canonicalize the load into several (struct_element_addr (load))
   // pairs.
-  using ProjInstPairTy = std::pair<Projection, SingleValueInstruction *>;
+
+  struct ProjInstPair {
+    Projection P;
+    SingleValueInstruction *I;
+
+    // When sorting, just look at the projection and ignore the instruction.
+    bool operator<(const ProjInstPair &RHS) const { return P < RHS.P; }
+  };
 
   // Go through the loads uses and add any users that are projections to the
   // projection list.
-  llvm::SmallVector<ProjInstPairTy, 8> Projections;
+  llvm::SmallVector<ProjInstPair, 8> Projections;
   for (auto *UI : getNonDebugUses(LI)) {
     auto *User = UI->getUser();
 
@@ -503,8 +510,8 @@ SILInstruction *SILCombiner::visitLoadInst(LoadInst *LI) {
   Projection *LastProj = nullptr;
   LoadInst *LastNewLoad = nullptr;
   for (auto &Pair : Projections) {
-    auto &Proj = Pair.first;
-    auto *Inst = Pair.second;
+    auto &Proj = Pair.P;
+    auto *Inst = Pair.I;
 
     // If this projection is the same as the last projection we processed, just
     // replace all uses of the projection with the load we created previously.

test/DebugInfo/compiler-flags.swift

@@ -21,3 +21,8 @@
 // CHECK-LLDB-NOT: debug_pubnames
 // CHECK-LLDB:     apple_names
 // CHECK-LLDB-NOT: debug_pubnames
+
+// Check that we don't write temporary file names in the debug info
+// RUN: TMPDIR=abc/def %target-swift-frontend %s -I abc/def/xyz -g -emit-ir -o - | %FileCheck --check-prefix CHECK-TEMP %s
+// CHECK-TEMP: !DICompileUnit({{.*}} flags: "{{.*}} -I <temporary-file>
+