[llvm-commits] CVS: llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp SelectionDAGISel.cpp

[Chris Lattner]

Changes in directory llvm/lib/CodeGen/SelectionDAG:

LegalizeDAG.cpp updated: 1.456 -> 1.457
SelectionDAGISel.cpp updated: 1.342 -> 1.343
---
Log message:

Teach TargetData to handle 'preferred' alignment for each target, and use 
these alignment amounts to align scalars when we can.  Patch by Scott Michel!



---
Diffs of the changes:  (+13 -15)

 LegalizeDAG.cpp      |   13 +++++++++----
 SelectionDAGISel.cpp |   15 ++++-----------
 2 files changed, 13 insertions(+), 15 deletions(-)


Index: llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
diff -u llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp:1.456 llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp:1.457
--- llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp:1.456	Fri Jan 19 15:13:56 2007
+++ llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp	Sat Jan 20 16:35:55 2007
@@ -3029,7 +3029,7 @@
         // new ones, as reuse may inhibit scheduling.
         const Type *Ty = MVT::getTypeForValueType(ExtraVT);
         unsigned TySize = (unsigned)TLI.getTargetData()->getTypeSize(Ty);
-        unsigned Align  = TLI.getTargetData()->getTypeAlignment(Ty);
+        unsigned Align  = TLI.getTargetData()->getTypeAlignmentPref(Ty);
         MachineFunction &MF = DAG.getMachineFunction();
         int SSFI =
           MF.getFrameInfo()->CreateStackObject((unsigned)TySize, Align);
@@ -3937,7 +3937,9 @@
 SDOperand SelectionDAGLegalize::CreateStackTemporary(MVT::ValueType VT) {
   MachineFrameInfo *FrameInfo = DAG.getMachineFunction().getFrameInfo();
   unsigned ByteSize = MVT::getSizeInBits(VT)/8;
-  int FrameIdx = FrameInfo->CreateStackObject(ByteSize, ByteSize);
+  const Type *Ty = MVT::getTypeForValueType(VT);
+  unsigned StackAlign = (unsigned)TLI.getTargetData()->getTypeAlignmentPref(Ty);
+  int FrameIdx = FrameInfo->CreateStackObject(ByteSize, StackAlign);
   return DAG.getFrameIndex(FrameIdx, TLI.getPointerTy());
 }
 
@@ -4242,9 +4244,12 @@
   if (Op0.getValueType() == MVT::i32) {
     // simple 32-bit [signed|unsigned] integer to float/double expansion
     
-    // get the stack frame index of a 8 byte buffer
+    // get the stack frame index of a 8 byte buffer, pessimistically aligned
     MachineFunction &MF = DAG.getMachineFunction();
-    int SSFI = MF.getFrameInfo()->CreateStackObject(8, 8);
+    const Type *F64Type = MVT::getTypeForValueType(MVT::f64);
+    unsigned StackAlign =
+      (unsigned)TLI.getTargetData()->getTypeAlignmentPref(F64Type);
+    int SSFI = MF.getFrameInfo()->CreateStackObject(8, StackAlign);
     // get address of 8 byte buffer
     SDOperand StackSlot = DAG.getFrameIndex(SSFI, TLI.getPointerTy());
     // word offset constant for Hi/Lo address computation


Index: llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
diff -u llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:1.342 llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:1.343
--- llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:1.342	Thu Jan 11 06:24:14 2007
+++ llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp	Sat Jan 20 16:35:55 2007
@@ -244,17 +244,9 @@
         const Type *Ty = AI->getAllocatedType();
         uint64_t TySize = TLI.getTargetData()->getTypeSize(Ty);
         unsigned Align = 
-          std::max((unsigned)TLI.getTargetData()->getTypeAlignment(Ty),
+          std::max((unsigned)TLI.getTargetData()->getTypeAlignmentPref(Ty),
                    AI->getAlignment());
 
-        // If the alignment of the value is smaller than the size of the 
-        // value, and if the size of the value is particularly small 
-        // (<= 8 bytes), round up to the size of the value for potentially 
-        // better performance.
-        //
-        // FIXME: This could be made better with a preferred alignment hook in
-        // TargetData.  It serves primarily to 8-byte align doubles for X86.
-        if (Align < TySize && TySize <= 8) Align = TySize;
         TySize *= CUI->getZExtValue();   // Get total allocated size.
         if (TySize == 0) TySize = 1; // Don't create zero-sized stack objects.
         StaticAllocaMap[AI] =
@@ -1729,8 +1721,9 @@
 
   const Type *Ty = I.getAllocatedType();
   uint64_t TySize = TLI.getTargetData()->getTypeSize(Ty);
-  unsigned Align = std::max((unsigned)TLI.getTargetData()->getTypeAlignment(Ty),
-                            I.getAlignment());
+  unsigned Align =
+    std::max((unsigned)TLI.getTargetData()->getTypeAlignmentPref(Ty),
+             I.getAlignment());
 
   SDOperand AllocSize = getValue(I.getArraySize());
   MVT::ValueType IntPtr = TLI.getPointerTy();