[safestack] Reapply r283248 after moving X86-targeted SafeStack tests into

the X86 subdirectory. Original commit message:

Requires a valid TargetMachine to be passed to the SafeStack pass.

Patch by Michael LeMay

Differential revision: http://reviews.llvm.org/D24896

llvm-svn: 284161

1 files changed, 6 insertions, 7 deletions

diff --git a/llvm/lib/CodeGen/SafeStack.cpp b/llvm/lib/CodeGen/SafeStack.cpp
index 2f934f5ae02..ed3fa8cd6ad 100644
--- a/llvm/lib/CodeGen/SafeStack.cpp
+++ b/llvm/lib/CodeGen/SafeStack.cpp
@@ -357,9 +357,8 @@ bool SafeStack::IsSafeStackAlloca(const Value *AllocaPtr, uint64_t AllocaSize) {
 
 Value *SafeStack::getOrCreateUnsafeStackPtr(IRBuilder<> &IRB, Function &F) {
   // Check if there is a target-specific location for the unsafe stack pointer.
-  if (TL)
-    if (Value *V = TL->getSafeStackPointerLocation(IRB))
-      return V;
+  if (Value *V = TL->getSafeStackPointerLocation(IRB))
+    return V;
 
   // Otherwise, assume the target links with compiler-rt, which provides a
   // thread-local variable with a magic name.
@@ -392,9 +391,7 @@ Value *SafeStack::getOrCreateUnsafeStackPtr(IRBuilder<> &IRB, Function &F) {
 }
 
 Value *SafeStack::getStackGuard(IRBuilder<> &IRB, Function &F) {
-  Value *StackGuardVar = nullptr;
-  if (TL)
-    StackGuardVar = TL->getIRStackGuard(IRB);
+  Value *StackGuardVar = TL->getIRStackGuard(IRB);
   if (!StackGuardVar)
     StackGuardVar =
         F.getParent()->getOrInsertGlobal("__stack_chk_guard", StackPtrTy);
@@ -751,7 +748,9 @@ bool SafeStack::runOnFunction(Function &F) {
     return false;
   }
 
-  TL = TM ? TM->getSubtargetImpl(F)->getTargetLowering() : nullptr;
+  if (!TM)
+    report_fatal_error("Target machine is required");
+  TL = TM->getSubtargetImpl(F)->getTargetLowering();
   SE = &getAnalysis<ScalarEvolutionWrapperPass>().getSE();
 
   ++NumFunctions;