1 //===- MipsSubtarget.cpp - Mips Subtarget Information -----------*- C++ -*-===//
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 //
10 // This file implements the Mips specific subclass of TargetSubtarget.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "MipsSubtarget.h"
15 #include "Mips.h"
16 #include "MipsGenSubtarget.inc"
17 #include "llvm/Module.h"
18 #include "llvm/Support/CommandLine.h"
19 using namespace llvm;
20 
21 static cl::opt<bool>
22 NotABICall("disable-mips-abicall", cl::Hidden,
23            cl::desc("Disable code for SVR4-style dynamic objects"));
24 static cl::opt<bool>
25 AbsoluteCall("enable-mips-absolute-call", cl::Hidden,
26              cl::desc("Enable absolute call within abicall"));
27 static cl::opt<unsigned>
28 SSThreshold("mips-ssection-threshold", cl::Hidden,
29             cl::desc("Small data and bss section threshold size (default=8)"),
30             cl::init(8));
31 
32 MipsSubtarget::MipsSubtarget(const TargetMachine &TM, const Module &M,
33                              const std::string &FS, bool little) :
34   MipsArchVersion(Mips1), MipsABI(O32), IsLittle(little), IsSingleFloat(false),
35   IsFP64bit(false), IsGP64bit(false), HasVFPU(false), HasABICall(true),
36   HasAbsoluteCall(false), IsLinux(true), HasSEInReg(false), HasCondMov(false),
37   HasMulDivAdd(false), HasMinMax(false), HasSwap(false), HasBitCount(false)
38 {
39   std::string CPU = "mips1";
40   MipsArchVersion = Mips1;
41 
42   // Parse features string.
43   ParseSubtargetFeatures(FS, CPU);
44   const std::string& TT = M.getTargetTriple();
45 
46   // Small section size threshold
47   SSectionThreshold = SSThreshold;
48 
49   // Is the target system Linux ?
50   if (TT.find("linux") == std::string::npos)
51     IsLinux = false;
52 
53   // When only the target triple is specified and is
54   // a allegrex target, set the features. We also match
55   // big and little endian allegrex cores (dont really
56   // know if a big one exists)
57   if (TT.find("mipsallegrex") != std::string::npos ||
58       TT.find("psp") != std::string::npos) {
59     MipsABI = EABI;
60     IsSingleFloat = true;
61     MipsArchVersion = Mips2;
62     HasVFPU = true; // Enables Allegrex Vector FPU (not supported yet)
63     HasSEInReg = true;
64     HasBitCount = true;
65     HasSwap = true;
66     HasCondMov = true;
67   }
68 
69   // Abicall is the default for O32 ABI, but is disabled within EABI and in
70   // static code.
71   if (NotABICall || isABI_EABI() || (TM.getRelocationModel() == Reloc::Static))
72     HasABICall = false;
73 
74   // TODO: disable when handling 64 bit symbols in the future.
75   if (HasABICall && AbsoluteCall)
76     HasAbsoluteCall = true;
77 }
78