MFC r263312:

Pull in r196939 from upstream llvm trunk (by Reid Kleckner):

  Reland "Fix miscompile of MS inline assembly with stack realignment"

  This re-lands commit r196876, which was reverted in r196879.

  The tests have been fixed to pass on platforms with a stack alignment
  larger than 4.

  Update to clang side tests will land shortly.

Pull in r196986 from upstream llvm trunk (by Reid Kleckner):

  Revert the backend fatal error from r196939

  The combination of inline asm, stack realignment, and dynamic allocas
  turns out to be too common to reject out of hand.

  ASan inserts empy inline asm fragments and uses aligned allocas.
  Compiling any trivial function containing a dynamic alloca with ASan is
  enough to trigger the check.

  XFAIL the test cases that would be miscompiled and add one that uses the
  relevant functionality.

Pull in r202930 from upstream llvm trunk (by Hans Wennborg):

  Check for dynamic allocas and inline asm that clobbers sp before building
  selection dag (PR19012)

  In X86SelectionDagInfo::EmitTargetCodeForMemcpy we check with MachineFrameInfo
  to make sure that ESI isn't used as a base pointer register before we choose to
  emit rep movs (which clobbers esi).

  The problem is that MachineFrameInfo wouldn't know about dynamic allocas or
  inline asm that clobbers the stack pointer until SelectionDAGBuilder has
  encountered them.

  This patch fixes the problem by checking for such things when building the
  FunctionLoweringInfo.

  Differential Revision: http://llvm-reviews.chandlerc.com/D2954

Together, these commits fix the problem encountered in the devel/emacs
port on the i386 architecture, where a combination of stack realignment,
alloca() and memcpy() could incidentally clobber the %esi register,
leading to segfaults in the temacs build-time utility.

See also: http://llvm.org/PR18171 and http://llvm.org/PR19012

Reported by:	ashish
PR:		ports/183064

MFC r263313:

Pull in r203311 from upstream llvm trunk (by Arnold Schwaighofer):

  ISel: Make VSELECT selection terminate in cases where the condition type has to
  be split and the result type widened.

  When the condition of a vselect has to be split it makes no sense widening the
  vselect and thereby widening the condition. We end up in an endless loop of
  widening (vselect result type) and splitting (condition mask type) doing this.
  Instead, split both the condition and the vselect and widen the result.

  I ran this over the test suite with i686 and mattr=+sse and saw no regressions.

  Fixes PR18036.

With this fix the original problem case from the graphics/rawtherapee
port (posted in http://llvm.org/PR18036 ) now compiles within ~97MB RSS.

Reported by:	mandree

MFC r263320:

Add separate patch files for all the customizations we have currently
applied to our copy of llvm/clang.  These can be applied in alphabetical
order to a pristine llvm/clang 3.4 release source tree, to result in the
same version used in FreeBSD.

This is intended to clearly document all the changes until now, which
mostly consist of cherry pickings from the respective upstream trunks,
plus a number of hand-written FreeBSD-specific ones.  Hopefully those
can eventually be cleaned up and sent upstream too.

1 files changed, 263 insertions, 0 deletions

diff --git a/contrib/llvm/patches/patch-r263312-llvm-r202930-fix-alloca-esi-clobber.diff b/contrib/llvm/patches/patch-r263312-llvm-r202930-fix-alloca-esi-clobber.diff
new file mode 100644
index 0000000..b4017c9
--- /dev/null
+++ b/contrib/llvm/patches/patch-r263312-llvm-r202930-fix-alloca-esi-clobber.diff
@@ -0,0 +1,263 @@
+Pull in r202930 from upstream llvm trunk (by Hans Wennborg):
+
+  Check for dynamic allocas and inline asm that clobbers sp before building
+  selection dag (PR19012)
+
+  In X86SelectionDagInfo::EmitTargetCodeForMemcpy we check with MachineFrameInfo
+  to make sure that ESI isn't used as a base pointer register before we choose to
+  emit rep movs (which clobbers esi).
+
+  The problem is that MachineFrameInfo wouldn't know about dynamic allocas or
+  inline asm that clobbers the stack pointer until SelectionDAGBuilder has
+  encountered them.
+
+  This patch fixes the problem by checking for such things when building the
+  FunctionLoweringInfo.
+
+  Differential Revision: http://llvm-reviews.chandlerc.com/D2954
+
+Introduced here: http://svn.freebsd.org/changeset/base/263312
+
+Index: lib/CodeGen/MachineFunction.cpp
+===================================================================
+--- lib/CodeGen/MachineFunction.cpp
++++ lib/CodeGen/MachineFunction.cpp
+@@ -525,13 +525,14 @@ int MachineFrameInfo::CreateSpillStackObject(uint6
+ /// variable sized object is created, whether or not the index returned is
+ /// actually used.
+ ///
+-int MachineFrameInfo::CreateVariableSizedObject(unsigned Alignment) {
++int MachineFrameInfo::CreateVariableSizedObject(unsigned Alignment,
++                                                const AllocaInst *Alloca) {
+   HasVarSizedObjects = true;
+   Alignment =
+     clampStackAlignment(!getFrameLowering()->isStackRealignable() ||
+                           !RealignOption,
+                         Alignment, getFrameLowering()->getStackAlignment()); 
+-  Objects.push_back(StackObject(0, Alignment, 0, false, false, true, 0));
++  Objects.push_back(StackObject(0, Alignment, 0, false, false, true, Alloca));
+   ensureMaxAlignment(Alignment);
+   return (int)Objects.size()-NumFixedObjects-1;
+ }
+Index: lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+===================================================================
+--- lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
++++ lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+@@ -419,7 +419,7 @@ bool SelectionDAGISel::runOnMachineFunction(Machin
+   SplitCriticalSideEffectEdges(const_cast<Function&>(Fn), this);
+ 
+   CurDAG->init(*MF, TTI, TLI);
+-  FuncInfo->set(Fn, *MF);
++  FuncInfo->set(Fn, *MF, CurDAG);
+ 
+   if (UseMBPI && OptLevel != CodeGenOpt::None)
+     FuncInfo->BPI = &getAnalysis<BranchProbabilityInfo>();
+@@ -429,7 +429,6 @@ bool SelectionDAGISel::runOnMachineFunction(Machin
+   SDB->init(GFI, *AA, LibInfo);
+ 
+   MF->setHasInlineAsm(false);
+-  MF->getFrameInfo()->setHasInlineAsmWithSPAdjust(false);
+ 
+   SelectAllBasicBlocks(Fn);
+ 
+Index: lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
+===================================================================
+--- lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
++++ lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
+@@ -33,6 +33,7 @@
+ #include "llvm/Support/ErrorHandling.h"
+ #include "llvm/Support/MathExtras.h"
+ #include "llvm/Target/TargetInstrInfo.h"
++#include "llvm/Target/TargetFrameLowering.h"
+ #include "llvm/Target/TargetLowering.h"
+ #include "llvm/Target/TargetOptions.h"
+ #include "llvm/Target/TargetRegisterInfo.h"
+@@ -55,7 +56,8 @@ static bool isUsedOutsideOfDefiningBlock(const Ins
+   return false;
+ }
+ 
+-void FunctionLoweringInfo::set(const Function &fn, MachineFunction &mf) {
++void FunctionLoweringInfo::set(const Function &fn, MachineFunction &mf,
++                               SelectionDAG *DAG) {
+   const TargetLowering *TLI = TM.getTargetLowering();
+ 
+   Fn = &fn;
+@@ -100,6 +102,43 @@ static bool isUsedOutsideOfDefiningBlock(const Ins
+   for (; BB != EB; ++BB)
+     for (BasicBlock::const_iterator I = BB->begin(), E = BB->end();
+          I != E; ++I) {
++      // Look for dynamic allocas.
++      if (const AllocaInst *AI = dyn_cast<AllocaInst>(I)) {
++        if (!AI->isStaticAlloca()) {
++          unsigned Align = std::max(
++              (unsigned)TLI->getDataLayout()->getPrefTypeAlignment(
++                AI->getAllocatedType()),
++              AI->getAlignment());
++          unsigned StackAlign = TM.getFrameLowering()->getStackAlignment();
++          if (Align <= StackAlign)
++            Align = 0;
++          // Inform the Frame Information that we have variable-sized objects.
++          MF->getFrameInfo()->CreateVariableSizedObject(Align ? Align : 1, AI);
++        }
++      }
++
++      // Look for inline asm that clobbers the SP register.
++      if (isa<CallInst>(I) || isa<InvokeInst>(I)) {
++        ImmutableCallSite CS(I);
++        if (const InlineAsm *IA = dyn_cast<InlineAsm>(CS.getCalledValue())) {
++          unsigned SP = TLI->getStackPointerRegisterToSaveRestore();
++          std::vector<TargetLowering::AsmOperandInfo> Ops =
++            TLI->ParseConstraints(CS);
++          for (size_t I = 0, E = Ops.size(); I != E; ++I) {
++            TargetLowering::AsmOperandInfo &Op = Ops[I];
++            if (Op.Type == InlineAsm::isClobber) {
++              // Clobbers don't have SDValue operands, hence SDValue().
++              TLI->ComputeConstraintToUse(Op, SDValue(), DAG);
++              std::pair<unsigned, const TargetRegisterClass*> PhysReg =
++                TLI->getRegForInlineAsmConstraint(Op.ConstraintCode,
++                                                  Op.ConstraintVT);
++              if (PhysReg.first == SP)
++                MF->getFrameInfo()->setHasInlineAsmWithSPAdjust(true);
++            }
++          }
++        }
++      }
++
+       // Mark values used outside their block as exported, by allocating
+       // a virtual register for them.
+       if (isUsedOutsideOfDefiningBlock(I))
+Index: lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+===================================================================
+--- lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
++++ lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+@@ -860,10 +860,10 @@ void RegsForValue::AddInlineAsmOperands(unsigned C
+       unsigned TheReg = Regs[Reg++];
+       Ops.push_back(DAG.getRegister(TheReg, RegisterVT));
+ 
+-      // Notice if we clobbered the stack pointer.  Yes, inline asm can do this.
+       if (TheReg == SP && Code == InlineAsm::Kind_Clobber) {
+-        MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
+-        MFI->setHasInlineAsmWithSPAdjust(true);
++        // If we clobbered the stack pointer, MFI should know about it.
++        assert(DAG.getMachineFunction().getFrameInfo()->
++            hasInlineAsmWithSPAdjust());
+       }
+     }
+   }
+@@ -3378,9 +3378,7 @@ void SelectionDAGBuilder::visitAlloca(const Alloca
+   setValue(&I, DSA);
+   DAG.setRoot(DSA.getValue(1));
+ 
+-  // Inform the Frame Information that we have just allocated a variable-sized
+-  // object.
+-  FuncInfo.MF->getFrameInfo()->CreateVariableSizedObject(Align ? Align : 1);
++  assert(FuncInfo.MF->getFrameInfo()->hasVarSizedObjects());
+ }
+ 
+ void SelectionDAGBuilder::visitLoad(const LoadInst &I) {
+Index: test/CodeGen/X86/stack-align-memcpy.ll
+===================================================================
+--- test/CodeGen/X86/stack-align-memcpy.ll
++++ test/CodeGen/X86/stack-align-memcpy.ll
+@@ -2,6 +2,9 @@
+ 
+ %struct.foo = type { [88 x i8] }
+ 
++declare void @bar(i8* nocapture, %struct.foo* align 4 byval) nounwind
++declare void @baz(i8*) nounwind
++
+ ; PR15249
+ ; We can't use rep;movsl here because it clobbers the base pointer in %esi.
+ define void @test1(%struct.foo* nocapture %x, i32 %y) nounwind {
+@@ -15,4 +18,26 @@ define void @test1(%struct.foo* nocapture %x, i32
+ ; CHECK-NOT: rep;movsl
+ }
+ 
+-declare void @bar(i8* nocapture, %struct.foo* align 4 byval) nounwind
++; PR19012
++; Also don't clobber %esi if the dynamic alloca comes after the memcpy.
++define void @test2(%struct.foo* nocapture %x, i32 %y, i8* %z) nounwind {
++  call void @bar(i8* %z, %struct.foo* align 4 byval %x)
++  %dynalloc = alloca i8, i32 %y, align 1
++  call void @baz(i8* %dynalloc)
++  ret void
++
++; CHECK-LABEL: test2:
++; CHECK: movl %esp, %esi
++; CHECK-NOT: rep;movsl
++}
++
++; Check that we do use rep movs if we make the alloca static.
++define void @test3(%struct.foo* nocapture %x, i32 %y, i8* %z) nounwind {
++  call void @bar(i8* %z, %struct.foo* align 4 byval %x)
++  %statalloc = alloca i8, i32 8, align 1
++  call void @baz(i8* %statalloc)
++  ret void
++
++; CHECK-LABEL: test3:
++; CHECK: rep;movsl
++}
+Index: test/CodeGen/X86/inline-asm-sp-clobber-memcpy.ll
+===================================================================
+--- test/CodeGen/X86/inline-asm-sp-clobber-memcpy.ll
++++ test/CodeGen/X86/inline-asm-sp-clobber-memcpy.ll
+@@ -0,0 +1,17 @@
++; RUN: llc < %s -force-align-stack -mtriple i386-apple-darwin -mcpu=i486 | FileCheck %s
++
++%struct.foo = type { [88 x i8] }
++
++declare void @bar(i8* nocapture, %struct.foo* align 4 byval) nounwind
++
++; PR19012
++; Don't clobber %esi if we have inline asm that clobbers %esp.
++define void @test1(%struct.foo* nocapture %x, i32 %y, i8* %z) nounwind {
++  call void @bar(i8* %z, %struct.foo* align 4 byval %x)
++  call void asm sideeffect inteldialect "xor esp, esp", "=*m,~{flags},~{esp},~{esp},~{dirflag},~{fpsr},~{flags}"(i8* %z)
++  ret void
++
++; CHECK-LABEL: test1:
++; CHECK: movl %esp, %esi
++; CHECK-NOT: rep;movsl
++}
+Index: include/llvm/CodeGen/FunctionLoweringInfo.h
+===================================================================
+--- include/llvm/CodeGen/FunctionLoweringInfo.h
++++ include/llvm/CodeGen/FunctionLoweringInfo.h
+@@ -41,6 +41,7 @@ class MachineBasicBlock;
+ class MachineFunction;
+ class MachineModuleInfo;
+ class MachineRegisterInfo;
++class SelectionDAG;
+ class TargetLowering;
+ class Value;
+ 
+@@ -125,7 +126,7 @@ class FunctionLoweringInfo {
+   /// set - Initialize this FunctionLoweringInfo with the given Function
+   /// and its associated MachineFunction.
+   ///
+-  void set(const Function &Fn, MachineFunction &MF);
++  void set(const Function &Fn, MachineFunction &MF, SelectionDAG *DAG);
+ 
+   /// clear - Clear out all the function-specific state. This returns this
+   /// FunctionLoweringInfo to an empty state, ready to be used for a
+Index: include/llvm/CodeGen/MachineFrameInfo.h
+===================================================================
+--- include/llvm/CodeGen/MachineFrameInfo.h
++++ include/llvm/CodeGen/MachineFrameInfo.h
+@@ -244,6 +244,7 @@ class MachineFrameInfo {
+     LocalFrameSize = 0;
+     LocalFrameMaxAlign = 0;
+     UseLocalStackAllocationBlock = false;
++    HasInlineAsmWithSPAdjust = false;
+   }
+ 
+   /// hasStackObjects - Return true if there are any stack objects in this
+@@ -529,7 +530,7 @@ class MachineFrameInfo {
+   /// variable sized object is created, whether or not the index returned is
+   /// actually used.
+   ///
+-  int CreateVariableSizedObject(unsigned Alignment);
++  int CreateVariableSizedObject(unsigned Alignment, const AllocaInst *Alloca);
+ 
+   /// getCalleeSavedInfo - Returns a reference to call saved info vector for the
+   /// current function.