Upgrade our copy of clang and llvm to 3.6.1 release.

This release contains the following cherry-picked revisions from
upstream trunk:

  226124 226151 226164 226165 226166 226407 226408 226409 226652
  226905 226983 227084 227087 227089 227208 227209 227210 227211
  227212 227213 227214 227269 227430 227482 227503 227519 227574
  227822 227986 227987 227988 227989 227990 228037 228038 228039
  228040 228188 228189 228190 228273 228372 228373 228374 228403
  228765 228848 228918 229223 229225 229226 229227 229228 229230
  229234 229235 229236 229238 229239 229413 229507 229680 229750
  229751 229752 229911 230146 230147 230235 230253 230255 230469
  230500 230564 230603 230657 230742 230748 230956 231219 231237
  231245 231259 231280 231451 231563 231601 231658 231659 231662
  231984 231986 232046 232085 232142 232176 232179 232189 232382
  232386 232389 232425 232438 232443 232675 232786 232797 232943
  232957 233075 233080 233351 233353 233409 233410 233508 233584
  233819 233904 234629 234636 234891 234975 234977 235524 235641
  235662 235931 236099 236306 236307

Please note that from 3.5.0 onwards, clang and llvm require C++11
support to build; see UPDATING for more information.

1 files changed, 59 insertions, 25 deletions

diff --git a/contrib/llvm/lib/Target/X86/X86FrameLowering.cpp b/contrib/llvm/lib/Target/X86/X86FrameLowering.cpp
index f2eb6a8..66f54e9 100644
--- a/contrib/llvm/lib/Target/X86/X86FrameLowering.cpp
+++ b/contrib/llvm/lib/Target/X86/X86FrameLowering.cpp
@@ -392,12 +392,25 @@ static bool usesTheStack(const MachineFunction &MF) {
   return false;
 }
 
-void X86FrameLowering::getStackProbeFunction(const X86Subtarget &STI,
-                                             unsigned &CallOp,
-                                             const char *&Symbol) {
-  CallOp = STI.is64Bit() ? X86::W64ALLOCA : X86::CALLpcrel32;
+void X86FrameLowering::emitStackProbeCall(MachineFunction &MF,
+                                          MachineBasicBlock &MBB,
+                                          MachineBasicBlock::iterator MBBI,
+                                          DebugLoc DL) {
+  const TargetInstrInfo &TII = *MF.getSubtarget().getInstrInfo();
+  const X86Subtarget &STI = MF.getTarget().getSubtarget<X86Subtarget>();
+  bool Is64Bit = STI.is64Bit();
+  bool IsLargeCodeModel = MF.getTarget().getCodeModel() == CodeModel::Large;
+  const X86RegisterInfo *RegInfo =
+      static_cast<const X86RegisterInfo *>(MF.getSubtarget().getRegisterInfo());
+
+  unsigned CallOp;
+  if (Is64Bit)
+    CallOp = IsLargeCodeModel ? X86::CALL64r : X86::CALL64pcrel32;
+  else
+    CallOp = X86::CALLpcrel32;
 
-  if (STI.is64Bit()) {
+  const char *Symbol;
+  if (Is64Bit) {
     if (STI.isTargetCygMing()) {
       Symbol = "___chkstk_ms";
     } else {
@@ -407,6 +420,37 @@ void X86FrameLowering::getStackProbeFunction(const X86Subtarget &STI,
     Symbol = "_alloca";
   else
     Symbol = "_chkstk";
+
+  MachineInstrBuilder CI;
+
+  // All current stack probes take AX and SP as input, clobber flags, and
+  // preserve all registers. x86_64 probes leave RSP unmodified.
+  if (Is64Bit && MF.getTarget().getCodeModel() == CodeModel::Large) {
+    // For the large code model, we have to call through a register. Use R11,
+    // as it is scratch in all supported calling conventions.
+    BuildMI(MBB, MBBI, DL, TII.get(X86::MOV64ri), X86::R11)
+        .addExternalSymbol(Symbol);
+    CI = BuildMI(MBB, MBBI, DL, TII.get(CallOp)).addReg(X86::R11);
+  } else {
+    CI = BuildMI(MBB, MBBI, DL, TII.get(CallOp)).addExternalSymbol(Symbol);
+  }
+
+  unsigned AX = Is64Bit ? X86::RAX : X86::EAX;
+  unsigned SP = Is64Bit ? X86::RSP : X86::ESP;
+  CI.addReg(AX, RegState::Implicit)
+      .addReg(SP, RegState::Implicit)
+      .addReg(AX, RegState::Define | RegState::Implicit)
+      .addReg(SP, RegState::Define | RegState::Implicit)
+      .addReg(X86::EFLAGS, RegState::Define | RegState::Implicit);
+
+  if (Is64Bit) {
+    // MSVC x64's __chkstk and cygwin/mingw's ___chkstk_ms do not adjust %rsp
+    // themselves. It also does not clobber %rax so we can reuse it when
+    // adjusting %rsp.
+    BuildMI(MBB, MBBI, DL, TII.get(X86::SUB64rr), X86::RSP)
+        .addReg(X86::RSP)
+        .addReg(X86::RAX);
+  }
 }
 
 /// emitPrologue - Push callee-saved registers onto the stack, which
@@ -739,11 +783,6 @@ void X86FrameLowering::emitPrologue(MachineFunction &MF) const {
   // increments is necessary to ensure that the guard pages used by the OS
   // virtual memory manager are allocated in correct sequence.
   if (NumBytes >= StackProbeSize && UseStackProbe) {
-    const char *StackProbeSymbol;
-    unsigned CallOp;
-
-    getStackProbeFunction(STI, CallOp, StackProbeSymbol);
-
     // Check whether EAX is livein for this function.
     bool isEAXAlive = isEAXLiveIn(MF);
 
@@ -772,22 +811,17 @@ void X86FrameLowering::emitPrologue(MachineFunction &MF) const {
         .setMIFlag(MachineInstr::FrameSetup);
     }
 
-    BuildMI(MBB, MBBI, DL,
-            TII.get(CallOp))
-      .addExternalSymbol(StackProbeSymbol)
-      .addReg(StackPtr,    RegState::Define | RegState::Implicit)
-      .addReg(X86::EFLAGS, RegState::Define | RegState::Implicit)
-      .setMIFlag(MachineInstr::FrameSetup);
+    // Save a pointer to the MI where we set AX.
+    MachineBasicBlock::iterator SetRAX = MBBI;
+    --SetRAX;
+
+    // Call __chkstk, __chkstk_ms, or __alloca.
+    emitStackProbeCall(MF, MBB, MBBI, DL);
+
+    // Apply the frame setup flag to all inserted instrs.
+    for (; SetRAX != MBBI; ++SetRAX)
+      SetRAX->setFlag(MachineInstr::FrameSetup);
 
-    if (Is64Bit) {
-      // MSVC x64's __chkstk and cygwin/mingw's ___chkstk_ms do not adjust %rsp
-      // themself. It also does not clobber %rax so we can reuse it when
-      // adjusting %rsp.
-      BuildMI(MBB, MBBI, DL, TII.get(X86::SUB64rr), StackPtr)
-        .addReg(StackPtr)
-        .addReg(X86::RAX)
-        .setMIFlag(MachineInstr::FrameSetup);
-    }
     if (isEAXAlive) {
       // Restore EAX
       MachineInstr *MI = addRegOffset(BuildMI(MF, DL, TII.get(X86::MOV32rm),