1 //===- AArch64TargetTransformInfo.cpp - AArch64 specific TTI pass ---------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 /// \file
10 /// This file implements a TargetTransformInfo analysis pass specific to the
11 /// AArch64 target machine. It uses the target's detailed information to provide
12 /// more precise answers to certain TTI queries, while letting the target
13 /// independent and default TTI implementations handle the rest.
14 ///
15 //===----------------------------------------------------------------------===//
16 
17 #define DEBUG_TYPE "aarch64tti"
18 #include "AArch64.h"
19 #include "AArch64TargetMachine.h"
20 #include "llvm/Analysis/TargetTransformInfo.h"
21 #include "llvm/Support/Debug.h"
22 #include "llvm/Target/CostTable.h"
23 #include "llvm/Target/TargetLowering.h"
24 using namespace llvm;
25 
26 // Declare the pass initialization routine locally as target-specific passes
27 // don't have a target-wide initialization entry point, and so we rely on the
28 // pass constructor initialization.
29 namespace llvm {
30 void initializeAArch64TTIPass(PassRegistry &);
31 }
32 
33 namespace {
34 
35 class AArch64TTI final : public ImmutablePass, public TargetTransformInfo {
36   const AArch64Subtarget *ST;
37   const AArch64TargetLowering *TLI;
38 
39 public:
40   AArch64TTI() : ImmutablePass(ID), ST(0), TLI(0) {
41     llvm_unreachable("This pass cannot be directly constructed");
42   }
43 
44   AArch64TTI(const AArch64TargetMachine *TM)
45       : ImmutablePass(ID), ST(TM->getSubtargetImpl()),
46         TLI(TM->getTargetLowering()) {
47     initializeAArch64TTIPass(*PassRegistry::getPassRegistry());
48   }
49 
50   virtual void initializePass() override {
51     pushTTIStack(this);
52   }
53 
54   virtual void getAnalysisUsage(AnalysisUsage &AU) const override {
55     TargetTransformInfo::getAnalysisUsage(AU);
56   }
57 
58   /// Pass identification.
59   static char ID;
60 
61   /// Provide necessary pointer adjustments for the two base classes.
62   virtual void *getAdjustedAnalysisPointer(const void *ID) override {
63     if (ID == &TargetTransformInfo::ID)
64       return (TargetTransformInfo*)this;
65     return this;
66   }
67 
68   /// \name Scalar TTI Implementations
69   /// @{
70 
71   /// @}
72 
73 
74   /// \name Vector TTI Implementations
75   /// @{
76 
77   unsigned getNumberOfRegisters(bool Vector) const {
78     if (Vector) {
79       if (ST->hasNEON())
80         return 32;
81       return 0;
82     }
83     return 32;
84   }
85 
86   unsigned getRegisterBitWidth(bool Vector) const {
87     if (Vector) {
88       if (ST->hasNEON())
89         return 128;
90       return 0;
91     }
92     return 64;
93   }
94 
95   unsigned getMaximumUnrollFactor() const override { return 2; }
96   /// @}
97 };
98 
99 } // end anonymous namespace
100 
101 INITIALIZE_AG_PASS(AArch64TTI, TargetTransformInfo, "aarch64tti",
102                    "AArch64 Target Transform Info", true, true, false)
103 char AArch64TTI::ID = 0;
104 
105 ImmutablePass *
106 llvm::createAArch64TargetTransformInfoPass(const AArch64TargetMachine *TM) {
107   return new AArch64TTI(TM);
108 }
109