Update llvm/clang to trunk r126547.

There are several bugfixes in this update, but the most important one is
to ensure __start_ and __stop_ symbols for linker sets and kernel module
metadata are always emitted in object files:

  http://llvm.org/bugs/show_bug.cgi?id=9292

Before this fix, if you compiled kernel modules with clang, they would
not be properly processed by kldxref, and if they had any dependencies,
the kernel would fail to load those.  Another problem occurred when
attempting to mount a tmpfs filesystem, which would result in 'operation
not supported by device'.

1 files changed, 26 insertions, 12 deletions

diff --git a/contrib/llvm/lib/Target/ARM/ARMFastISel.cpp b/contrib/llvm/lib/Target/ARM/ARMFastISel.cpp
index 9f29530..26f48b3 100644
--- a/contrib/llvm/lib/Target/ARM/ARMFastISel.cpp
+++ b/contrib/llvm/lib/Target/ARM/ARMFastISel.cpp
@@ -172,6 +172,7 @@ class ARMFastISel : public FastISel {
     unsigned ARMMaterializeGV(const GlobalValue *GV, EVT VT);
     unsigned ARMMoveToFPReg(EVT VT, unsigned SrcReg);
     unsigned ARMMoveToIntReg(EVT VT, unsigned SrcReg);
+    unsigned ARMSelectCallOp(const GlobalValue *GV);
 
     // Call handling routines.
   private:
@@ -1633,6 +1634,25 @@ bool ARMFastISel::SelectRet(const Instruction *I) {
   return true;
 }
 
+unsigned ARMFastISel::ARMSelectCallOp(const GlobalValue *GV) {
+
+  // Depend our opcode for thumb on whether or not we're targeting an
+  // externally callable function. For libcalls we'll just pass a NULL GV
+  // in here.
+  bool isExternal = false;
+  if (!GV || GV->hasExternalLinkage()) isExternal = true;
+  
+  // Darwin needs the r9 versions of the opcodes.
+  bool isDarwin = Subtarget->isTargetDarwin();
+  if (isThumb && isExternal) {
+    return isDarwin ? ARM::tBLXi_r9 : ARM::tBLXi;
+  } else if (isThumb) {
+    return isDarwin ? ARM::tBLr9 : ARM::tBL;
+  } else  {
+    return isDarwin ? ARM::BLr9 : ARM::BL;
+  }
+}
+
 // A quick function that will emit a call for a named libcall in F with the
 // vector of passed arguments for the Instruction in I. We can assume that we
 // can emit a call for any libcall we can produce. This is an abridged version
@@ -1694,20 +1714,17 @@ bool ARMFastISel::ARMEmitLibcall(const Instruction *I, RTLIB::Libcall Call) {
   // Issue the call, BLXr9 for darwin, BLX otherwise. This uses V5 ops.
   // TODO: Turn this into the table of arm call ops.
   MachineInstrBuilder MIB;
-  unsigned CallOpc;
-  if(isThumb) {
-    CallOpc = Subtarget->isTargetDarwin() ? ARM::tBLXi_r9 : ARM::tBLXi;
+  unsigned CallOpc = ARMSelectCallOp(NULL);
+  if(isThumb)
     // Explicitly adding the predicate here.
     MIB = AddDefaultPred(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
                          TII.get(CallOpc)))
                          .addExternalSymbol(TLI.getLibcallName(Call));
-  } else {
-    CallOpc = Subtarget->isTargetDarwin() ? ARM::BLr9 : ARM::BL;
+  else
     // Explicitly adding the predicate here.
     MIB = AddDefaultPred(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
                          TII.get(CallOpc))
           .addExternalSymbol(TLI.getLibcallName(Call)));
-  }
 
   // Add implicit physical register uses to the call.
   for (unsigned i = 0, e = RegArgs.size(); i != e; ++i)
@@ -1813,21 +1830,18 @@ bool ARMFastISel::SelectCall(const Instruction *I) {
   // Issue the call, BLXr9 for darwin, BLX otherwise. This uses V5 ops.
   // TODO: Turn this into the table of arm call ops.
   MachineInstrBuilder MIB;
-  unsigned CallOpc;
+  unsigned CallOpc = ARMSelectCallOp(GV);
   // Explicitly adding the predicate here.
-  if(isThumb) {
-    CallOpc = Subtarget->isTargetDarwin() ? ARM::tBLXi_r9 : ARM::tBLXi;
+  if(isThumb)
     // Explicitly adding the predicate here.
     MIB = AddDefaultPred(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
                          TII.get(CallOpc)))
           .addGlobalAddress(GV, 0, 0);
-  } else {
-    CallOpc = Subtarget->isTargetDarwin() ? ARM::BLr9 : ARM::BL;
+  else
     // Explicitly adding the predicate here.
     MIB = AddDefaultPred(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
                          TII.get(CallOpc))
           .addGlobalAddress(GV, 0, 0));
-  }
   
   // Add implicit physical register uses to the call.
   for (unsigned i = 0, e = RegArgs.size(); i != e; ++i)