xref: /freebsd/contrib/llvm-project/llvm/lib/Target/Sparc/SparcSubtarget.cpp (revision 59c8e88e72633afbc47a4ace0d2170d00d51f7dc)
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/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(StringRef CPU,
29                                                                 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   // Parse features string.
36   ParseSubtargetFeatures(CPUName, /*TuneCPU*/ CPUName, FS);
37 
38   // Popc is a v9-only instruction.
39   if (!IsV9)
40     UsePopc = false;
41 
42   return *this;
43 }
44 
45 SparcSubtarget::SparcSubtarget(const Triple &TT, const std::string &CPU,
46                                const std::string &FS, const TargetMachine &TM,
47                                bool is64Bit)
48     : SparcGenSubtargetInfo(TT, CPU, /*TuneCPU*/ CPU, FS), TargetTriple(TT),
49       Is64Bit(is64Bit), InstrInfo(initializeSubtargetDependencies(CPU, FS)),
50       TLInfo(TM, *this), FrameLowering(*this) {}
51 
52 int SparcSubtarget::getAdjustedFrameSize(int frameSize) const {
53 
54   if (is64Bit()) {
55     // All 64-bit stack frames must be 16-byte aligned, and must reserve space
56     // for spilling the 16 window registers at %sp+BIAS..%sp+BIAS+128.
57     frameSize += 128;
58     // Frames with calls must also reserve space for 6 outgoing arguments
59     // whether they are used or not. LowerCall_64 takes care of that.
60     frameSize = alignTo(frameSize, 16);
61   } else {
62     // Emit the correct save instruction based on the number of bytes in
63     // the frame. Minimum stack frame size according to V8 ABI is:
64     //   16 words for register window spill
65     //    1 word for address of returned aggregate-value
66     // +  6 words for passing parameters on the stack
67     // ----------
68     //   23 words * 4 bytes per word = 92 bytes
69     frameSize += 92;
70 
71     // Round up to next doubleword boundary -- a double-word boundary
72     // is required by the ABI.
73     frameSize = alignTo(frameSize, 8);
74   }
75   return frameSize;
76 }
77 
78 bool SparcSubtarget::enableMachineScheduler() const {
79   return true;
80 }
81