xref: /freebsd/contrib/llvm-project/llvm/lib/Target/Sparc/SparcSubtarget.cpp (revision a90b9d0159070121c221b966469c3e36d912bf82)
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 "Sparc.h"
15 #include "llvm/ADT/StringRef.h"
16 #include "llvm/MC/TargetRegistry.h"
17 #include "llvm/Support/MathExtras.h"
18 
19 using namespace llvm;
20 
21 #define DEBUG_TYPE "sparc-subtarget"
22 
23 #define GET_SUBTARGETINFO_TARGET_DESC
24 #define GET_SUBTARGETINFO_CTOR
25 #include "SparcGenSubtargetInfo.inc"
26 
27 void SparcSubtarget::anchor() { }
28 
29 SparcSubtarget &SparcSubtarget::initializeSubtargetDependencies(
30     StringRef CPU, StringRef TuneCPU, StringRef FS) {
31   // Determine default and user specified characteristics
32   std::string CPUName = std::string(CPU);
33   if (CPUName.empty())
34     CPUName = (Is64Bit) ? "v9" : "v8";
35 
36   if (TuneCPU.empty())
37     TuneCPU = CPUName;
38 
39   // Parse features string.
40   ParseSubtargetFeatures(CPUName, TuneCPU, FS);
41 
42   // Popc is a v9-only instruction.
43   if (!IsV9)
44     UsePopc = false;
45 
46   return *this;
47 }
48 
49 SparcSubtarget::SparcSubtarget(const StringRef &CPU, const StringRef &TuneCPU,
50                                const StringRef &FS, const TargetMachine &TM,
51                                bool is64Bit)
52     : SparcGenSubtargetInfo(TM.getTargetTriple(), CPU, TuneCPU, FS),
53       ReserveRegister(TM.getMCRegisterInfo()->getNumRegs()),
54       TargetTriple(TM.getTargetTriple()), Is64Bit(is64Bit),
55       InstrInfo(initializeSubtargetDependencies(CPU, TuneCPU, FS)),
56       TLInfo(TM, *this), FrameLowering(*this) {}
57 
58 int SparcSubtarget::getAdjustedFrameSize(int frameSize) const {
59 
60   if (is64Bit()) {
61     // All 64-bit stack frames must be 16-byte aligned, and must reserve space
62     // for spilling the 16 window registers at %sp+BIAS..%sp+BIAS+128.
63     frameSize += 128;
64     // Frames with calls must also reserve space for 6 outgoing arguments
65     // whether they are used or not. LowerCall_64 takes care of that.
66     frameSize = alignTo(frameSize, 16);
67   } else {
68     // Emit the correct save instruction based on the number of bytes in
69     // the frame. Minimum stack frame size according to V8 ABI is:
70     //   16 words for register window spill
71     //    1 word for address of returned aggregate-value
72     // +  6 words for passing parameters on the stack
73     // ----------
74     //   23 words * 4 bytes per word = 92 bytes
75     frameSize += 92;
76 
77     // Round up to next doubleword boundary -- a double-word boundary
78     // is required by the ABI.
79     frameSize = alignTo(frameSize, 8);
80   }
81   return frameSize;
82 }
83 
84 bool SparcSubtarget::enableMachineScheduler() const {
85   return true;
86 }
87