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diff --git a/contrib/llvm/lib/Target/ARM/ARMBasicBlockInfo.h b/contrib/llvm/lib/Target/ARM/ARMBasicBlockInfo.h
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+//===-- ARMBasicBlockInfo.h - Basic Block Information -----------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Utility functions and data structure for computing block size.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_TARGET_ARM_ARMBASICBLOCKINFO_H
+#define LLVM_LIB_TARGET_ARM_ARMBASICBLOCKINFO_H
+
+#include "ARM.h"
+#include "ARMMachineFunctionInfo.h"
+using namespace llvm;
+
+namespace llvm {
+
+/// UnknownPadding - Return the worst case padding that could result from
+/// unknown offset bits. This does not include alignment padding caused by
+/// known offset bits.
+///
+/// @param LogAlign log2(alignment)
+/// @param KnownBits Number of known low offset bits.
+inline unsigned UnknownPadding(unsigned LogAlign, unsigned KnownBits) {
+ if (KnownBits < LogAlign)
+ return (1u << LogAlign) - (1u << KnownBits);
+ return 0;
+}
+
+/// BasicBlockInfo - Information about the offset and size of a single
+/// basic block.
+struct BasicBlockInfo {
+ /// Offset - Distance from the beginning of the function to the beginning
+ /// of this basic block.
+ ///
+ /// Offsets are computed assuming worst case padding before an aligned
+ /// block. This means that subtracting basic block offsets always gives a
+ /// conservative estimate of the real distance which may be smaller.
+ ///
+ /// Because worst case padding is used, the computed offset of an aligned
+ /// block may not actually be aligned.
+ unsigned Offset;
+
+ /// Size - Size of the basic block in bytes. If the block contains
+ /// inline assembly, this is a worst case estimate.
+ ///
+ /// The size does not include any alignment padding whether from the
+ /// beginning of the block, or from an aligned jump table at the end.
+ unsigned Size;
+
+ /// KnownBits - The number of low bits in Offset that are known to be
+ /// exact. The remaining bits of Offset are an upper bound.
+ uint8_t KnownBits;
+
+ /// Unalign - When non-zero, the block contains instructions (inline asm)
+ /// of unknown size. The real size may be smaller than Size bytes by a
+ /// multiple of 1 << Unalign.
+ uint8_t Unalign;
+
+ /// PostAlign - When non-zero, the block terminator contains a .align
+ /// directive, so the end of the block is aligned to 1 << PostAlign
+ /// bytes.
+ uint8_t PostAlign;
+
+ BasicBlockInfo() : Offset(0), Size(0), KnownBits(0), Unalign(0),
+ PostAlign(0) {}
+
+ /// Compute the number of known offset bits internally to this block.
+ /// This number should be used to predict worst case padding when
+ /// splitting the block.
+ unsigned internalKnownBits() const {
+ unsigned Bits = Unalign ? Unalign : KnownBits;
+ // If the block size isn't a multiple of the known bits, assume the
+ // worst case padding.
+ if (Size & ((1u << Bits) - 1))
+ Bits = countTrailingZeros(Size);
+ return Bits;
+ }
+
+ /// Compute the offset immediately following this block. If LogAlign is
+ /// specified, return the offset the successor block will get if it has
+ /// this alignment.
+ unsigned postOffset(unsigned LogAlign = 0) const {
+ unsigned PO = Offset + Size;
+ unsigned LA = std::max(unsigned(PostAlign), LogAlign);
+ if (!LA)
+ return PO;
+ // Add alignment padding from the terminator.
+ return PO + UnknownPadding(LA, internalKnownBits());
+ }
+
+ /// Compute the number of known low bits of postOffset. If this block
+ /// contains inline asm, the number of known bits drops to the
+ /// instruction alignment. An aligned terminator may increase the number
+ /// of know bits.
+ /// If LogAlign is given, also consider the alignment of the next block.
+ unsigned postKnownBits(unsigned LogAlign = 0) const {
+ return std::max(std::max(unsigned(PostAlign), LogAlign),
+ internalKnownBits());
+ }
+};
+
+} // end namespace llvm
+
+#endif
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