Revert "Roll Clang 218707:223109 (+r223211, +r223219, -r220714)" and follow-ups.

tools/clang/scripts/update.sh

Index: tools/clang/scripts/update.sh
diff --git a/tools/clang/scripts/update.sh b/tools/clang/scripts/update.sh
index b585440238b105018bda05007ac5d4bbefa7f584..ad534adb9c50acdccaa2aa58cc5bd6e09fe04b2d 100755
--- a/tools/clang/scripts/update.sh
+++ b/tools/clang/scripts/update.sh
@@ -8,7 +8,7 @@
 # Do NOT CHANGE this if you don't know what you're doing -- see
 # https://code.google.com/p/chromium/wiki/UpdatingClang
 # Reverting problematic clang rolls is safe, though.
-CLANG_REVISION=223109
+CLANG_REVISION=218707
 
 THIS_DIR="$(dirname "${0}")"
 LLVM_DIR="${THIS_DIR}/../../../third_party/llvm"
@@ -238,15 +238,8 @@ for i in \
       "${LLVM_DIR}/test/DebugInfo/gmlt.ll" \
       "${LLVM_DIR}/lib/CodeGen/SpillPlacement.cpp" \
       "${LLVM_DIR}/lib/CodeGen/SpillPlacement.h" \
-      "${LLVM_DIR}/lib/Transforms/Instrumentation/MemorySanitizer.cpp" \
-      "${CLANG_DIR}/test/Driver/env.c" \
-      "${CLANG_DIR}/lib/Frontend/InitPreprocessor.cpp" \
-      "${CLANG_DIR}/test/Frontend/exceptions.c" \
-      "${CLANG_DIR}/test/Preprocessor/predefined-exceptions.m" \
-      "${LLVM_DIR}/test/Bindings/Go/go.test" \
       ; do
   if [[ -e "${i}" ]]; then
-    rm -f "${i}"  # For unversioned files.
     svn revert "${i}"
   fi;
 done
@@ -324,141 +317,177 @@ EOF
 patch -p0
 popd
 
-# Apply r223211: "Revert r222997."
+# Apply r218742: test: XFAIL the non-darwin gmlt test on darwin
+# Back-ported becase the test was renamed.
 pushd "${LLVM_DIR}"
 cat << 'EOF' |
---- a/lib/Transforms/Instrumentation/MemorySanitizer.cpp
-+++ b/lib/Transforms/Instrumentation/MemorySanitizer.cpp
-@@ -921,8 +921,6 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
-             Value *OriginPtr =
-                 getOriginPtrForArgument(&FArg, EntryIRB, ArgOffset);
-             setOrigin(A, EntryIRB.CreateLoad(OriginPtr));
--          } else {
--            setOrigin(A, getCleanOrigin());
-           }
-         }
-         ArgOffset += RoundUpToAlignment(Size, kShadowTLSAlignment);
-@@ -942,13 +940,15 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
-   /// \brief Get the origin for a value.
-   Value *getOrigin(Value *V) {
-     if (!MS.TrackOrigins) return nullptr;
--    if (!PropagateShadow) return getCleanOrigin();
--    if (isa<Constant>(V)) return getCleanOrigin();
--    assert((isa<Instruction>(V) || isa<Argument>(V)) &&
--           "Unexpected value type in getOrigin()");
--    Value *Origin = OriginMap[V];
--    assert(Origin && "Missing origin");
--    return Origin;
-+    if (isa<Instruction>(V) || isa<Argument>(V)) {
-+      Value *Origin = OriginMap[V];
-+      if (!Origin) {
-+        DEBUG(dbgs() << "NO ORIGIN: " << *V << "\n");
-+        Origin = getCleanOrigin();
-+      }
-+      return Origin;
-+    }
-+    return getCleanOrigin();
-   }
- 
-   /// \brief Get the origin for i-th argument of the instruction I.
-@@ -1088,7 +1088,6 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
-     IRB.CreateStore(getCleanShadow(&I), ShadowPtr);
- 
-     setShadow(&I, getCleanShadow(&I));
--    setOrigin(&I, getCleanOrigin());
-   }
- 
-   void visitAtomicRMWInst(AtomicRMWInst &I) {
+--- a/test/DebugInfo/gmlt.ll
++++ b/test/DebugInfo/gmlt.ll
+@@ -1,2 +1,5 @@
+ ; REQUIRES: object-emission
+ ; RUN: %llc_dwarf -O0 -filetype=obj < %S/Inputs/gmlt.ll | llvm-dwarfdump - | FileCheck %S/Inputs/gmlt.ll
++
++; There's a darwin specific test in X86/gmlt, so it's okay to XFAIL this here.
++; XFAIL: darwin
 EOF
 patch -p1
 popd
 
-# Apply r223219: "Preserve LD_LIBRARY_PATH when using the 'env' command"
-pushd "${CLANG_DIR}"
-cat << 'EOF' |
---- a/test/Driver/env.c
-+++ b/test/Driver/env.c
-@@ -5,12 +5,14 @@
- // REQUIRES: shell
- //
- // The PATH variable is heavily used when trying to find a linker.
--// RUN: env -i LC_ALL=C %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
-+// RUN: env -i LC_ALL=C LD_LIBRARY_PATH="$LD_LIBRARY_PATH" \
-+// RUN:   %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
- // RUN:     --target=i386-unknown-linux \
- // RUN:     --sysroot=%S/Inputs/basic_linux_tree \
- // RUN:   | FileCheck --check-prefix=CHECK-LD-32 %s
- //
--// RUN: env -i LC_ALL=C PATH="" %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
-+// RUN: env -i LC_ALL=C PATH="" LD_LIBRARY_PATH="$LD_LIBRARY_PATH" \
-+// RUN:   %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
- // RUN:     --target=i386-unknown-linux \
- // RUN:     --sysroot=%S/Inputs/basic_linux_tree \
- // RUN:   | FileCheck --check-prefix=CHECK-LD-32 %s
-EOF
-patch -p1
-popd
-
-# Revert r220714: "Frontend: Define __EXCEPTIONS if -fexceptions is passed"
-pushd "${CLANG_DIR}"
+# Apply r218921; fixes spill placement compile-time regression.
+pushd "${LLVM_DIR}"
 cat << 'EOF' |
---- a/lib/Frontend/InitPreprocessor.cpp
-+++ b/lib/Frontend/InitPreprocessor.cpp
-@@ -566,7 +566,7 @@ static void InitializePredefinedMacros(const TargetInfo &TI,
-     Builder.defineMacro("__BLOCKS__");
+--- a/lib/CodeGen/SpillPlacement.cpp
++++ b/lib/CodeGen/SpillPlacement.cpp
+@@ -61,27 +61,6 @@ void SpillPlacement::getAnalysisUsage(AnalysisUsage &AU) const {
+   MachineFunctionPass::getAnalysisUsage(AU);
+ }
+ 
+-namespace {
+-static ManagedStatic<BlockFrequency> Threshold;
+-}
+-
+-/// Decision threshold. A node gets the output value 0 if the weighted sum of
+-/// its inputs falls in the open interval (-Threshold;Threshold).
+-static BlockFrequency getThreshold() { return *Threshold; }
+-
+-/// \brief Set the threshold for a given entry frequency.
+-///
+-/// Set the threshold relative to \c Entry.  Since the threshold is used as a
+-/// bound on the open interval (-Threshold;Threshold), 1 is the minimum
+-/// threshold.
+-static void setThreshold(const BlockFrequency &Entry) {
+-  // Apparently 2 is a good threshold when Entry==2^14, but we need to scale
+-  // it.  Divide by 2^13, rounding as appropriate.
+-  uint64_t Freq = Entry.getFrequency();
+-  uint64_t Scaled = (Freq >> 13) + bool(Freq & (1 << 12));
+-  *Threshold = std::max(UINT64_C(1), Scaled);
+-}
+-
+ /// Node - Each edge bundle corresponds to a Hopfield node.
+ ///
+ /// The node contains precomputed frequency data that only depends on the CFG,
+@@ -127,9 +106,9 @@ struct SpillPlacement::Node {
+ 
+   /// clear - Reset per-query data, but preserve frequencies that only depend on
+   // the CFG.
+-  void clear() {
++  void clear(const BlockFrequency &Threshold) {
+     BiasN = BiasP = Value = 0;
+-    SumLinkWeights = getThreshold();
++    SumLinkWeights = Threshold;
+     Links.clear();
    }
  
--  if (!LangOpts.MSVCCompat && LangOpts.Exceptions)
-+  if (!LangOpts.MSVCCompat && LangOpts.CXXExceptions)
-     Builder.defineMacro("__EXCEPTIONS");
-   if (!LangOpts.MSVCCompat && LangOpts.RTTI)
-     Builder.defineMacro("__GXX_RTTI");
-diff --git a/test/Frontend/exceptions.c b/test/Frontend/exceptions.c
-index 981b5b9..4bbaaa3 100644
---- a/test/Frontend/exceptions.c
-+++ b/test/Frontend/exceptions.c
-@@ -1,9 +1,6 @@
--// RUN: %clang_cc1 -fms-compatibility -fexceptions -fcxx-exceptions -DMS_MODE -verify %s
-+// RUN: %clang_cc1 -fms-compatibility -fexceptions -fcxx-exceptions -verify %s
- // expected-no-diagnostics
+@@ -167,7 +146,7 @@ struct SpillPlacement::Node {
  
--// RUN: %clang_cc1 -fms-compatibility -fexceptions -verify %s
--// expected-no-diagnostics
--
--#if defined(MS_MODE) && defined(__EXCEPTIONS)
-+#if defined(__EXCEPTIONS)
- #error __EXCEPTIONS should not be defined.
- #endif
-diff --git a/test/Preprocessor/predefined-exceptions.m b/test/Preprocessor/predefined-exceptions.m
-index 0791075..c13f429 100644
---- a/test/Preprocessor/predefined-exceptions.m
-+++ b/test/Preprocessor/predefined-exceptions.m
-@@ -1,6 +1,6 @@
- // RUN: %clang_cc1 -x objective-c -fobjc-exceptions -fexceptions -E -dM %s | FileCheck -check-prefix=CHECK-OBJC-NOCXX %s 
- // CHECK-OBJC-NOCXX: #define OBJC_ZEROCOST_EXCEPTIONS 1
--// CHECK-OBJC-NOCXX: #define __EXCEPTIONS 1
-+// CHECK-OBJC-NOCXX-NOT: #define __EXCEPTIONS 1
+   /// update - Recompute Value from Bias and Links. Return true when node
+   /// preference changes.
+-  bool update(const Node nodes[]) {
++  bool update(const Node nodes[], const BlockFrequency &Threshold) {
+     // Compute the weighted sum of inputs.
+     BlockFrequency SumN = BiasN;
+     BlockFrequency SumP = BiasP;
+@@ -187,9 +166,9 @@ struct SpillPlacement::Node {
+     //  2. It helps tame rounding errors when the links nominally sum to 0.
+     //
+     bool Before = preferReg();
+-    if (SumN >= SumP + getThreshold())
++    if (SumN >= SumP + Threshold)
+       Value = -1;
+-    else if (SumP >= SumN + getThreshold())
++    else if (SumP >= SumN + Threshold)
+       Value = 1;
+     else
+       Value = 0;
+@@ -228,7 +207,7 @@ void SpillPlacement::activate(unsigned n) {
+   if (ActiveNodes->test(n))
+     return;
+   ActiveNodes->set(n);
+-  nodes[n].clear();
++  nodes[n].clear(Threshold);
  
- // RUN: %clang_cc1 -x objective-c++ -fobjc-exceptions -fexceptions -fcxx-exceptions -E -dM %s | FileCheck -check-prefix=CHECK-OBJC-CXX %s 
- // CHECK-OBJC-CXX: #define OBJC_ZEROCOST_EXCEPTIONS 1
-EOF
-patch -p1
-popd
-
-# This Go bindings test doesn't work after the bootstrap build on Linux. (PR21552)
-pushd "${LLVM_DIR}"
-cat << 'EOF' |
-Index: test/Bindings/Go/go.test
-===================================================================
---- test/Bindings/Go/go.test    (revision 223109)
-+++ test/Bindings/Go/go.test    (working copy)
-@@ -1,3 +1,3 @@
--; RUN: llvm-go test llvm.org/llvm/bindings/go/llvm
-+; RUN: true
+   // Very large bundles usually come from big switches, indirect branches,
+   // landing pads, or loops with many 'continue' statements. It is difficult to
+@@ -245,6 +224,18 @@ void SpillPlacement::activate(unsigned n) {
+   }
+ }
+ 
++/// \brief Set the threshold for a given entry frequency.
++///
++/// Set the threshold relative to \c Entry.  Since the threshold is used as a
++/// bound on the open interval (-Threshold;Threshold), 1 is the minimum
++/// threshold.
++void SpillPlacement::setThreshold(const BlockFrequency &Entry) {
++  // Apparently 2 is a good threshold when Entry==2^14, but we need to scale
++  // it.  Divide by 2^13, rounding as appropriate.
++  uint64_t Freq = Entry.getFrequency();
++  uint64_t Scaled = (Freq >> 13) + bool(Freq & (1 << 12));
++  Threshold = std::max(UINT64_C(1), Scaled);
++}
+ 
+ /// addConstraints - Compute node biases and weights from a set of constraints.
+ /// Set a bit in NodeMask for each active node.
+@@ -311,7 +302,7 @@ bool SpillPlacement::scanActiveBundles() {
+   Linked.clear();
+   RecentPositive.clear();
+   for (int n = ActiveNodes->find_first(); n>=0; n = ActiveNodes->find_next(n)) {
+-    nodes[n].update(nodes);
++    nodes[n].update(nodes, Threshold);
+     // A node that must spill, or a node without any links is not going to
+     // change its value ever again, so exclude it from iterations.
+     if (nodes[n].mustSpill())
+@@ -331,7 +322,7 @@ void SpillPlacement::iterate() {
+   // First update the recently positive nodes. They have likely received new
+   // negative bias that will turn them off.
+   while (!RecentPositive.empty())
+-    nodes[RecentPositive.pop_back_val()].update(nodes);
++    nodes[RecentPositive.pop_back_val()].update(nodes, Threshold);
+ 
+   if (Linked.empty())
+     return;
+@@ -350,7 +341,7 @@ void SpillPlacement::iterate() {
+            iteration == 0 ? Linked.rbegin() : std::next(Linked.rbegin()),
+            E = Linked.rend(); I != E; ++I) {
+       unsigned n = *I;
+-      if (nodes[n].update(nodes)) {
++      if (nodes[n].update(nodes, Threshold)) {
+         Changed = true;
+         if (nodes[n].preferReg())
+           RecentPositive.push_back(n);
+@@ -364,7 +355,7 @@ void SpillPlacement::iterate() {
+     for (SmallVectorImpl<unsigned>::const_iterator I =
+            std::next(Linked.begin()), E = Linked.end(); I != E; ++I) {
+       unsigned n = *I;
+-      if (nodes[n].update(nodes)) {
++      if (nodes[n].update(nodes, Threshold)) {
+         Changed = true;
+         if (nodes[n].preferReg())
+           RecentPositive.push_back(n);
+diff --git a/lib/CodeGen/SpillPlacement.h b/lib/CodeGen/SpillPlacement.h
+index 03cf5cd..622361e 100644
+--- a/lib/CodeGen/SpillPlacement.h
++++ b/lib/CodeGen/SpillPlacement.h
+@@ -62,6 +62,10 @@ class SpillPlacement : public MachineFunctionPass {
+   // Block frequencies are computed once. Indexed by block number.
+   SmallVector<BlockFrequency, 8> BlockFrequencies;
+ 
++  /// Decision threshold. A node gets the output value 0 if the weighted sum of
++  /// its inputs falls in the open interval (-Threshold;Threshold).
++  BlockFrequency Threshold;
++
+ public:
+   static char ID; // Pass identification, replacement for typeid.
  
- ; REQUIRES: shell
+@@ -152,6 +156,7 @@ private:
+   void releaseMemory() override;
+ 
+   void activate(unsigned);
++  void setThreshold(const BlockFrequency &Entry);
+ };
+ 
+ } // end namespace llvm
 EOF
-patch -p0
+patch -p1
 popd