xref: /llvm-project/llvm/lib/Target/Sparc/SparcSubtarget.cpp (revision ed8019d9fbed2e6a6b08f8f73e9fa54a24f3ed52)
1 //===-- SparcSubtarget.cpp - SPARC Subtarget Information ------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file implements the SPARC specific subclass of TargetSubtargetInfo.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "SparcSubtarget.h"
14 #include "llvm/ADT/StringRef.h"
15 #include "llvm/MC/TargetRegistry.h"
16 #include "llvm/Support/MathExtras.h"
17 
18 using namespace llvm;
19 
20 #define DEBUG_TYPE "sparc-subtarget"
21 
22 #define GET_SUBTARGETINFO_TARGET_DESC
23 #define GET_SUBTARGETINFO_CTOR
24 #include "SparcGenSubtargetInfo.inc"
25 
26 void SparcSubtarget::anchor() { }
27 
28 SparcSubtarget &SparcSubtarget::initializeSubtargetDependencies(
29     StringRef CPU, StringRef TuneCPU, StringRef FS) {
30   // Determine default and user specified characteristics
31   std::string CPUName = std::string(CPU);
32   if (CPUName.empty())
33     CPUName = (Is64Bit) ? "v9" : "v8";
34 
35   if (TuneCPU.empty())
36     TuneCPU = CPUName;
37 
38   // Parse features string.
39   ParseSubtargetFeatures(CPUName, TuneCPU, FS);
40 
41   // Popc is a v9-only instruction.
42   if (!IsV9)
43     UsePopc = false;
44 
45   return *this;
46 }
47 
48 SparcSubtarget::SparcSubtarget(const StringRef &CPU, const StringRef &TuneCPU,
49                                const StringRef &FS, const TargetMachine &TM,
50                                bool is64Bit)
51     : SparcGenSubtargetInfo(TM.getTargetTriple(), CPU, TuneCPU, FS),
52       ReserveRegister(TM.getMCRegisterInfo()->getNumRegs()),
53       TargetTriple(TM.getTargetTriple()), Is64Bit(is64Bit),
54       InstrInfo(initializeSubtargetDependencies(CPU, TuneCPU, FS)),
55       TLInfo(TM, *this), FrameLowering(*this) {}
56 
57 int SparcSubtarget::getAdjustedFrameSize(int frameSize) const {
58 
59   if (is64Bit()) {
60     // All 64-bit stack frames must be 16-byte aligned, and must reserve space
61     // for spilling the 16 window registers at %sp+BIAS..%sp+BIAS+128.
62     frameSize += 128;
63     // Frames with calls must also reserve space for 6 outgoing arguments
64     // whether they are used or not. LowerCall_64 takes care of that.
65     frameSize = alignTo(frameSize, 16);
66   } else {
67     // Emit the correct save instruction based on the number of bytes in
68     // the frame. Minimum stack frame size according to V8 ABI is:
69     //   16 words for register window spill
70     //    1 word for address of returned aggregate-value
71     // +  6 words for passing parameters on the stack
72     // ----------
73     //   23 words * 4 bytes per word = 92 bytes
74     frameSize += 92;
75 
76     // Round up to next doubleword boundary -- a double-word boundary
77     // is required by the ABI.
78     frameSize = alignTo(frameSize, 8);
79   }
80   return frameSize;
81 }
82 
83 bool SparcSubtarget::enableMachineScheduler() const {
84   return true;
85 }
86