1 //===-- PPCLinux.cpp - PowerPC ToolChain Implementations --------*- C++ -*-===//
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 #include "PPCLinux.h"
10 #include "clang/Driver/Driver.h"
11 #include "clang/Driver/DriverDiagnostic.h"
12 #include "clang/Driver/Options.h"
13 #include "llvm/Support/FileSystem.h"
14 #include "llvm/Support/Path.h"
15 
16 using namespace clang::driver;
17 using namespace clang::driver::toolchains;
18 using namespace llvm::opt;
19 using namespace llvm::sys;
20 
21 // Glibc older than 2.32 doesn't fully support IEEE float128. Here we check
22 // glibc version by looking at dynamic linker name.
23 static bool GlibcSupportsFloat128(const std::string &Linker) {
24   llvm::SmallVector<char, 16> Path;
25 
26   // Resolve potential symlinks to linker.
27   if (fs::real_path(Linker, Path))
28     return false;
29   llvm::StringRef LinkerName =
30       path::filename(llvm::StringRef(Path.data(), Path.size()));
31 
32   // Since glibc 2.34, the installed .so file is not symlink anymore. But we can
33   // still safely assume it's newer than 2.32.
34   if (LinkerName.startswith("ld64.so"))
35     return true;
36 
37   if (!LinkerName.startswith("ld-2."))
38     return false;
39   unsigned Minor = (LinkerName[5] - '0') * 10 + (LinkerName[6] - '0');
40   if (Minor < 32)
41     return false;
42 
43   return true;
44 }
45 
46 PPCLinuxToolChain::PPCLinuxToolChain(const Driver &D,
47                                      const llvm::Triple &Triple,
48                                      const llvm::opt::ArgList &Args)
49     : Linux(D, Triple, Args) {
50   if (Arg *A = Args.getLastArg(options::OPT_mabi_EQ)) {
51     StringRef ABIName = A->getValue();
52 
53     if ((ABIName == "ieeelongdouble" &&
54          !SupportIEEEFloat128(D, Triple, Args)) ||
55         (ABIName == "ibmlongdouble" && !supportIBMLongDouble(D, Args)))
56       D.Diag(diag::warn_drv_unsupported_float_abi_by_lib) << ABIName;
57   }
58 }
59 
60 void PPCLinuxToolChain::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
61                                                   ArgStringList &CC1Args) const {
62   if (!DriverArgs.hasArg(clang::driver::options::OPT_nostdinc) &&
63       !DriverArgs.hasArg(options::OPT_nobuiltininc)) {
64     const Driver &D = getDriver();
65     SmallString<128> P(D.ResourceDir);
66     llvm::sys::path::append(P, "include", "ppc_wrappers");
67     addSystemInclude(DriverArgs, CC1Args, P);
68   }
69 
70   Linux::AddClangSystemIncludeArgs(DriverArgs, CC1Args);
71 }
72 
73 bool PPCLinuxToolChain::supportIBMLongDouble(
74     const Driver &D, const llvm::opt::ArgList &Args) const {
75   if (Args.hasArg(options::OPT_nostdlib, options::OPT_nostdlibxx))
76     return true;
77 
78   CXXStdlibType StdLib = ToolChain::GetCXXStdlibType(Args);
79   if (StdLib == CST_Libstdcxx)
80     return true;
81 
82   return StdLib == CST_Libcxx && !defaultToIEEELongDouble();
83 }
84 
85 bool PPCLinuxToolChain::SupportIEEEFloat128(
86     const Driver &D, const llvm::Triple &Triple,
87     const llvm::opt::ArgList &Args) const {
88   if (!Triple.isLittleEndian() || !Triple.isPPC64())
89     return false;
90 
91   if (Args.hasArg(options::OPT_nostdlib, options::OPT_nostdlibxx))
92     return true;
93 
94   CXXStdlibType StdLib = ToolChain::GetCXXStdlibType(Args);
95   bool HasUnsupportedCXXLib =
96       (StdLib == CST_Libcxx && !defaultToIEEELongDouble()) ||
97       (StdLib == CST_Libstdcxx &&
98        GCCInstallation.getVersion().isOlderThan(12, 1, 0));
99 
100   std::string Linker = Linux::getDynamicLinker(Args);
101   return GlibcSupportsFloat128((Twine(D.DyldPrefix) + Linker).str()) &&
102          !(D.CCCIsCXX() && HasUnsupportedCXXLib);
103 }
104