1 files changed, 13 insertions, 1 deletions
diff --git a/lib/CodeGen/MachineBlockPlacement.cpp b/lib/CodeGen/MachineBlockPlacement.cpp
index 3b09c6b779..bfba503b35 100644
--- a/lib/CodeGen/MachineBlockPlacement.cpp
+++ b/lib/CodeGen/MachineBlockPlacement.cpp
@@ -39,6 +39,7 @@
 #include "llvm/CodeGen/MachineLoopInfo.h"
 #include "llvm/CodeGen/MachineModuleInfo.h"
 #include "llvm/Support/Allocator.h"
+#include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Target/TargetInstrInfo.h"
 #include "llvm/Target/TargetLowering.h"
@@ -52,6 +53,11 @@ STATISTIC(CondBranchTakenFreq,
 STATISTIC(UncondBranchTakenFreq,
           "Potential frequency of taking unconditional branches");
 
+static cl::opt<unsigned> AlignAllBlock("align-all-blocks",
+                                       cl::desc("Force the alignment of all "
+                                                "blocks in the function."),
+                                       cl::init(0), cl::Hidden);
+
 namespace {
 class BlockChain;
 /// \brief Type for our function-wide basic block -> block chain mapping.
@@ -1061,7 +1067,7 @@ void MachineBlockPlacement::buildCFGChains(MachineFunction &F) {
     }
 
     // Align this block if the layout predecessor's edge into this block is
-    // cold relative to the block. When this is true, othe predecessors make up
+    // cold relative to the block. When this is true, other predecessors make up
     // all of the hot entries into the block and thus alignment is likely to be
     // important.
     BranchProbability LayoutProb = MBPI->getEdgeProbability(LayoutPred, *BI);
@@ -1088,6 +1094,12 @@ bool MachineBlockPlacement::runOnMachineFunction(MachineFunction &F) {
   BlockToChain.clear();
   ChainAllocator.DestroyAll();
 
+  if (AlignAllBlock)
+    // Align all of the blocks in the function to a specific alignment.
+    for (MachineFunction::iterator FI = F.begin(), FE = F.end();
+         FI != FE; ++FI)
+      FI->setAlignment(AlignAllBlock);
+
   // We always return true as we have no way to track whether the final order
   // differs from the original order.
   return true;