[X86][PowerPC] Support -mlong-double-128

[MaskRay]

Summary

This patch makes the driver option -mlong-double-128 available for X86
and PowerPC. The CC1 option -mlong-double-128 is available on all targets
for users to test on unsupported targets.

On PowerPC, -mlong-double-128 uses the IBM extended double format
because we don't support -mabi=ieeelongdouble.

[MaskRay]

Add a driver test

[MaskRay]

Small adjustment to PPC.cpp to make -mlong-double-128 -mabi=ieeelongdouble simpler

[MaskRay]

test/OpenMP/nvptx_unsupported_type_codegen.cpp

79 ↗

(On Diff #208266)

@ABataev The mangling scheme of __float128 is broken on x86 before this patch. For some reason the two lines no longer apply.. I assume you can fix this test properly :)

[ABataev]

test/OpenMP/nvptx_unsupported_type_codegen.cpp

79 ↗

(On Diff #208266)

You mean, these lines are not generated anymore? If so, it means that you broke compatibility between the host and device codegen with this patch.

[MaskRay]

test/OpenMP/nvptx_unsupported_type_codegen.cpp

79 ↗

(On Diff #208266)

The two lines are not generated. Can you help fix the test? The mangling scheme of __float128 is incorrect without this patch. If the test relies on that, it should be fixed. I know little about openmp+nvidia to understand what's going on..

[ABataev]

test/OpenMP/nvptx_unsupported_type_codegen.cpp

79 ↗

(On Diff #208266)

Sure, will try to send additional changes next week, most probably on Monday. Does this work for you?

[MaskRay]

test/OpenMP/nvptx_unsupported_type_codegen.cpp

79 ↗

(On Diff #208266)

Thanks!

[MaskRay]

Rebase

[MaskRay]

Rebase after getMangledCodeOfLongDouble -> getLongDoubleMangling rename

[ABataev]

test/OpenMP/nvptx_unsupported_type_codegen.cpp

79 ↗

(On Diff #208266)

Hi, I have a fix for the problem revealed with your patch, will commit it tomorrow. After this, I hope, the problem with the test will disappear.

[ABataev]

test/OpenMP/nvptx_unsupported_type_codegen.cpp

79 ↗

(On Diff #208266)

I fixed the problem, try to update the patch, the test should pass with your changes.

[MaskRay]

Rebase

The openmp issue was fixed by r365485

[MaskRay]

Ping:) It'll be great to have D64277 (-mlong-double-128) D64282 (libcall) D64283 (-mabi=ieeelongdouble) before 9.0.0 is branched.

[rnk]

lgtm with suggestion

lib/Driver/ToolChains/Clang.cpp

4009

There should be a shorthand for passing through the argument, A->render() or something.

[MaskRay]

Use A->render(Args, CmdArgs);

include/clang/Driver/Options.td

 def malign_functions_EQ : Joined<["-"], "malign-functions=">, Group<clang_ignored_m_Group>;
 def malign_loops_EQ : Joined<["-"], "malign-loops=">, Group<clang_ignored_m_Group>;
 def malign_jumps_EQ : Joined<["-"], "malign-jumps=">, Group<clang_ignored_m_Group>;
 def mfancy_math_387 : Flag<["-"], "mfancy-math-387">, Group<clang_ignored_m_Group>;
 def mlong_calls : Flag<["-"], "mlong-calls">, Group<m_Group>,
   HelpText<"Generate branches with extended addressability, usually via indirect jumps.">;
 def mlong_double_64 : Flag<["-"], "mlong-double-64">, Group<f_Group>, Flags<[CC1Option]>,
   HelpText<"Force long double to be 64 bits">;
+def mlong_double_128 : Flag<["-"], "mlong-double-128">, Group<f_Group>, Flags<[CC1Option]>,
+  HelpText<"Force long double to be 128 bits">;
 def mno_long_calls : Flag<["-"], "mno-long-calls">, Group<m_Group>,
   HelpText<"Restore the default behaviour of not generating long calls">;
 def mexecute_only : Flag<["-"], "mexecute-only">, Group<m_arm_Features_Group>,
   HelpText<"Disallow generation of data access to code sections (ARM only)">;
 def mno_execute_only : Flag<["-"], "mno-execute-only">, Group<m_arm_Features_Group>,
   HelpText<"Allow generation of data access to code sections (ARM only)">;
 def mtp_mode_EQ : Joined<["-"], "mtp=">, Group<m_arm_Features_Group>, Values<"soft,cp15,el0,el1,el2,el3">,
   HelpText<"Thread pointer access method (AArch32/AArch64 only)">;

lib/Basic/TargetInfo.cpp

if (Opts.OpenCL) {
     IntMaxType = SignedLongLong;
     Int64Type = SignedLong;
 
     HalfFormat = &llvm::APFloat::IEEEhalf();
     FloatFormat = &llvm::APFloat::IEEEsingle();
     LongDoubleFormat = &llvm::APFloat::IEEEquad();
   }
 
-  if (Opts.LongDoubleSize && Opts.LongDoubleSize == DoubleWidth) {
+  if (Opts.LongDoubleSize) {
+    if (Opts.LongDoubleSize == DoubleWidth) {
       LongDoubleWidth = DoubleWidth;
       LongDoubleAlign = DoubleAlign;
       LongDoubleFormat = DoubleFormat;
+    } else if (Opts.LongDoubleSize == 128) {
+      LongDoubleWidth = LongDoubleAlign = 128;
+      LongDoubleFormat = &llvm::APFloat::IEEEquad();
+    }
   }
 
   if (Opts.NewAlignOverride)
     NewAlign = Opts.NewAlignOverride * getCharWidth();
 
   // Each unsigned fixed point type has the same number of fractional bits as
   // its corresponding signed type.
   PaddingOnUnsignedFixedPoint |= Opts.PaddingOnUnsignedFixedPoint;

lib/Basic/Targets/PPC.cpp

 void PPCTargetInfo::fillValidCPUList(SmallVectorImpl<StringRef> &Values) const {
   Values.append(std::begin(ValidCPUNames), std::end(ValidCPUNames));
 }
 
 void PPCTargetInfo::adjust(LangOptions &Opts) {
   if (HasAltivec)
     Opts.AltiVec = 1;
   TargetInfo::adjust(Opts);
+  if (LongDoubleFormat != &llvm::APFloat::IEEEdouble())
+    LongDoubleFormat = &llvm::APFloat::PPCDoubleDouble();
 }
 
 ArrayRef<Builtin::Info> PPCTargetInfo::getTargetBuiltins() const {
   return llvm::makeArrayRef(BuiltinInfo, clang::PPC::LastTSBuiltin -
                                              Builtin::FirstTSBuiltin);
 }

lib/Basic/Targets/X86.h

#include "clang/Basic/X86Target.def"
   enum FPMathKind { FP_Default, FP_SSE, FP_387 } FPMath = FP_Default;
 
 public:
   X86TargetInfo(const llvm::Triple &Triple, const TargetOptions &)
       : TargetInfo(Triple) {
     LongDoubleFormat = &llvm::APFloat::x87DoubleExtended();
   }
 
+  const char *getLongDoubleMangling() const override {
+    return LongDoubleFormat == &llvm::APFloat::IEEEquad() ? "g" : "e";
+  }
+
   unsigned getFloatEvalMethod() const override {
     // X87 evaluates with 80 bits "long double" precision.
     return SSELevel == NoSSE ? 2 : 0;
   }
 
   ArrayRef<const char *> getGCCRegNames() const override;
 
   ArrayRef<TargetInfo::GCCRegAlias> getGCCRegAliases() const override {

 // x86_64 Android target
 class LLVM_LIBRARY_VISIBILITY AndroidX86_64TargetInfo
     : public LinuxTargetInfo<X86_64TargetInfo> {
 public:
   AndroidX86_64TargetInfo(const llvm::Triple &Triple, const TargetOptions &Opts)
       : LinuxTargetInfo<X86_64TargetInfo>(Triple, Opts) {
     LongDoubleFormat = &llvm::APFloat::IEEEquad();
   }
-
-  const char *getLongDoubleMangling() const override { return "g"; }
 };
 } // namespace targets
 } // namespace clang
 #endif // LLVM_CLANG_LIB_BASIC_TARGETS_X86_H

lib/Driver/ToolChains/Clang.cpp

Args.AddLastArg(CmdArgs, options::OPT_ffine_grained_bitfield_accesses,
                   options::OPT_fno_fine_grained_bitfield_accesses);
 
   // Handle segmented stacks.
   if (Args.hasArg(options::OPT_fsplit_stack))
     CmdArgs.push_back("-split-stacks");
 
   RenderFloatingPointOptions(TC, D, OFastEnabled, Args, CmdArgs);
 
-  if (Arg *A = Args.getLastArg(options::OPT_mlong_double_64)) {
+  if (Arg *A = Args.getLastArg(options::OPT_mlong_double_64,
+                               options::OPT_mlong_double_128)) {
     if (TC.getArch() == llvm::Triple::x86 ||
         TC.getArch() == llvm::Triple::x86_64 ||
         TC.getArch() == llvm::Triple::ppc || TC.getTriple().isPPC64()) {
-      CmdArgs.push_back("-mlong-double-64");
+      CmdArgs.push_back(A->getOption().matches(options::OPT_mlong_double_64)
+                            ? "-mlong-double-64"
+                            : "-mlong-double-128");
     } else {
       D.Diag(diag::err_drv_unsupported_opt_for_target)
           << A->getAsString(Args) << TripleStr;
     }
   }
 
   // Decide whether to use verbose asm. Verbose assembly is the default on
   // toolchains which have the integrated assembler on by default.

lib/Frontend/CompilerInvocation.cpp

#include "clang/Frontend/LangStandards.def"
   Opts.ObjCDefaultSynthProperties =
     !Args.hasArg(OPT_disable_objc_default_synthesize_properties);
   Opts.EncodeExtendedBlockSig =
     Args.hasArg(OPT_fencode_extended_block_signature);
   Opts.EmitAllDecls = Args.hasArg(OPT_femit_all_decls);
   Opts.PackStruct = getLastArgIntValue(Args, OPT_fpack_struct_EQ, 0, Diags);
   Opts.MaxTypeAlign = getLastArgIntValue(Args, OPT_fmax_type_align_EQ, 0, Diags);
   Opts.AlignDouble = Args.hasArg(OPT_malign_double);
-  Opts.LongDoubleSize = Args.hasArg(OPT_mlong_double_64) ? 64 : 0;
+  Opts.LongDoubleSize = Args.hasArg(OPT_mlong_double_128)
+                            ? 128
+                            : Args.hasArg(OPT_mlong_double_64) ? 64 : 0;
   Opts.PICLevel = getLastArgIntValue(Args, OPT_pic_level, 0, Diags);
   Opts.ROPI = Args.hasArg(OPT_fropi);
   Opts.RWPI = Args.hasArg(OPT_frwpi);
   Opts.PIE = Args.hasArg(OPT_pic_is_pie);
   Opts.Static = Args.hasArg(OPT_static_define);
   Opts.DumpRecordLayoutsSimple = Args.hasArg(OPT_fdump_record_layouts_simple);
   Opts.DumpRecordLayouts = Opts.DumpRecordLayoutsSimple
                         || Args.hasArg(OPT_fdump_record_layouts);

test/CodeGen/ppc64-long-double.cpp

 // RUN: %clang_cc1 -triple powerpc64-linux-musl -emit-llvm -o - %s | \
 // RUN:   FileCheck --check-prefix=FP64 %s
 // RUN: %clang_cc1 -triple powerpc64-linux-gnu -emit-llvm -o - %s -mlong-double-64 | \
 // RUN:   FileCheck --check-prefix=FP64 %s
+
 // RUN: %clang_cc1 -triple powerpc64-linux-gnu -emit-llvm -o - %s | \
 // RUN:   FileCheck --check-prefix=IBM128 %s
+// RUN: %clang_cc1 -triple powerpc64-linux-musl -emit-llvm -o - -mlong-double-128 %s | \
+// RUN:   FileCheck --check-prefix=IBM128 %s
 
 long double x = 0;
 int size = sizeof(x);
 
 // FP64: @x = global double {{.*}}, align 8
 // FP64: @size = global i32 8
 // IBM128: @x = global ppc_fp128 {{.*}}, align 16
 // IBM128: @size = global i32 16
 
 long double foo(long double d) { return d; }
 
 // FP64: double @_Z3fooe(double %d)
 // IBM128: ppc_fp128 @_Z3foog(ppc_fp128 %d)

test/CodeGen/x86-long-double.cpp

 // RUN:   FileCheck --check-prefixes=FP64,FP64-X32 %s
 // RUN: %clang_cc1 %s -emit-llvm -o - -triple=i686-apple-darwin -mlong-double-64 | \
 // RUN:   FileCheck --check-prefixes=FP64,FP64-X32 %s
 // RUN: %clang_cc1 %s -emit-llvm -o - -triple=x86_64 -mlong-double-64 | \
 // RUN:   FileCheck --check-prefixes=FP64,FP64-X64 %s
 // RUN: %clang_cc1 %s -emit-llvm -o - -triple=x86_64-apple-darwin -mlong-double-64 | \
 // RUN:   FileCheck --check-prefixes=FP64,FP64-X64 %s
 
+// RUN: %clang_cc1 %s -emit-llvm -o - -triple=i686 -mlong-double-128 | \
+// RUN:   FileCheck --check-prefix=FP128 %s
+// RUN: %clang_cc1 %s -emit-llvm -o - -triple=i686-apple-darwin -mlong-double-128 | \
+// RUN:   FileCheck --check-prefix=FP128 %s
+// RUN: %clang_cc1 %s -emit-llvm -o - -triple=x86_64 -mlong-double-128 | \
+// RUN:   FileCheck --check-prefix=FP128 %s
+// RUN: %clang_cc1 %s -emit-llvm -o - -triple=x86_64-apple-darwin -mlong-double-128 | \
+// RUN:   FileCheck --check-prefix=FP128 %s
+
 // Check -malign-double increases the alignment from 4 to 8 on x86-32.
 // RUN: %clang_cc1 %s -emit-llvm -o - -triple=i686 -mlong-double-64 \
 // RUN:   -malign-double | FileCheck --check-prefixes=FP64,FP64-X64 %s
 // RUN: %clang_cc1 %s -emit-llvm -o - -triple=x86_64 -mlong-double-64 \
 // RUN:   -malign-double | FileCheck --check-prefixes=FP64,FP64-X64 %s
 
 long double x = 0;
 int size = sizeof(x);
 
 // FP80-ELF32: @x = global x86_fp80 {{.*}}, align 4
 // FP80-ELF32: @size = global i32 12
 // FP80-ELF64: @x = global x86_fp80 {{.*}}, align 16
 // FP80-ELF64: @size = global i32 16
 // FP80-DARWIN: @x = global x86_fp80 {{.*}}, align 16
 // FP80-DARWIN: @size = global i32 16
 
 // FP64-X32: @x = global double {{.*}}, align 4
 // FP64-X32: @size = global i32 8
 // FP64-X64: @x = global double {{.*}}, align 8
 // FP64-X64: @size = global i32 8
 
+// FP128: @x = global fp128 {{.*}}, align 16
+// FP128: @size = global i32 16
+
 long double foo(long double d) { return d; }
 
 // FP64: double @_Z3fooe(double %d)
 // FP80: x86_fp80 @_Z3fooe(x86_fp80 %d)
+// FP128: fp128 @_Z3foog(fp128 %d)

test/Driver/mlong-double-128.c

+// RUN: %clang -target powerpc-linux-musl -c -### %s -mlong-double-128 2>&1 | FileCheck %s
+// RUN: %clang -target powerpc64-pc-freebsd12 -c -### %s -mlong-double-128 2>&1 | FileCheck %s
+// RUN: %clang -target powerpc64le-linux-musl -c -### %s -mlong-double-128 2>&1 | FileCheck %s
+// RUN: %clang -target i686-linux-gnu -c -### %s -mlong-double-128 2>&1 | FileCheck %s
+// RUN: %clang -target x86_64-linux-musl -c -### %s -mlong-double-128 2>&1 | FileCheck %s
+
+// CHECK: "-mlong-double-128"
+
+// RUN: %clang -target aarch64 -c -### %s -mlong-double-128 2>&1 | FileCheck --check-prefix=ERR %s
+
+// ERR: error: unsupported option '-mlong-double-128' for target 'aarch64'