[X86] Combine (cmov (and/or (setcc) (setcc))) into (cmov (cmov)).

[oota-llvm.git] / lib / Target / PowerPC / PPCBranchSelector.cpp

diff --git a/lib/Target/PowerPC/PPCBranchSelector.cpp b/lib/Target/PowerPC/PPCBranchSelector.cpp
index 9276211de7762a1272e9375a9c76d1fbf0976869..940d55ac1f36e68cb0a29c5f7bf8ecc8ee9e6bc1 100644 (file)
--- a/lib/Target/PowerPC/PPCBranchSelector.cpp
+++ b/lib/Target/PowerPC/PPCBranchSelector.cpp
@@ -15,7 +15,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-#define DEBUG_TYPE "ppc-branch-select"
 #include "PPC.h"
 #include "MCTargetDesc/PPCPredicates.h"
 #include "PPCInstrBuilder.h"
@@ -24,8 +23,11 @@
 #include "llvm/CodeGen/MachineFunctionPass.h"
 #include "llvm/Support/MathExtras.h"
 #include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetSubtargetInfo.h"
 using namespace llvm;
 
+#define DEBUG_TYPE "ppc-branch-select"
+
 STATISTIC(NumExpanded, "Number of branches expanded to long format");
 
 namespace llvm {
@@ -42,9 +44,9 @@ namespace {
     /// BlockSizes - The sizes of the basic blocks in the function.
     std::vector<unsigned> BlockSizes;
 
-    virtual bool runOnMachineFunction(MachineFunction &Fn);
+    bool runOnMachineFunction(MachineFunction &Fn) override;
 
-    virtual const char *getPassName() const {
+    const char *getPassName() const override {
       return "PowerPC Branch Selector";
     }
   };
@@ -63,17 +65,42 @@ FunctionPass *llvm::createPPCBranchSelectionPass() {
 
 bool PPCBSel::runOnMachineFunction(MachineFunction &Fn) {
   const PPCInstrInfo *TII =
-                static_cast<const PPCInstrInfo*>(Fn.getTarget().getInstrInfo());
+      static_cast<const PPCInstrInfo *>(Fn.getSubtarget().getInstrInfo());
   // Give the blocks of the function a dense, in-order, numbering.
   Fn.RenumberBlocks();
   BlockSizes.resize(Fn.getNumBlockIDs());
 
+  auto GetAlignmentAdjustment =
+    [TII](MachineBasicBlock &MBB, unsigned Offset) -> unsigned {
+    unsigned Align = MBB.getAlignment();
+    if (!Align)
+      return 0;
+
+    unsigned AlignAmt = 1 << Align;
+    unsigned ParentAlign = MBB.getParent()->getAlignment();
+
+    if (Align <= ParentAlign)
+      return OffsetToAlignment(Offset, AlignAmt);
+
+    // The alignment of this MBB is larger than the function's alignment, so we
+    // can't tell whether or not it will insert nops. Assume that it will.
+    return AlignAmt + OffsetToAlignment(Offset, AlignAmt);
+  };
+
   // Measure each MBB and compute a size for the entire function.
   unsigned FuncSize = 0;
   for (MachineFunction::iterator MFI = Fn.begin(), E = Fn.end(); MFI != E;
        ++MFI) {
     MachineBasicBlock *MBB = MFI;
 
+    // The end of the previous block may have extra nops if this block has an
+    // alignment requirement.
+    if (MBB->getNumber() > 0) {
+      unsigned AlignExtra = GetAlignmentAdjustment(*MBB, FuncSize);
+      BlockSizes[MBB->getNumber()-1] += AlignExtra;
+      FuncSize += AlignExtra;
+    }
+
     unsigned BlockSize = 0;
     for (MachineBasicBlock::iterator MBBI = MBB->begin(), EE = MBB->end();
          MBBI != EE; ++MBBI)
@@ -112,7 +139,7 @@ bool PPCBSel::runOnMachineFunction(MachineFunction &Fn) {
       unsigned MBBStartOffset = 0;
       for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end();
            I != E; ++I) {
-        MachineBasicBlock *Dest = 0;
+        MachineBasicBlock *Dest = nullptr;
         if (I->getOpcode() == PPC::BCC && !I->getOperand(2).isImm())
           Dest = I->getOperand(2).getMBB();
         else if ((I->getOpcode() == PPC::BC || I->getOpcode() == PPC::BCn) &&