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

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 yet (D64283).

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D64277

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@365866 91177308-0d34-0410-b5e6-96231b3b80d8

9 files changed, 52 insertions, 12 deletions

diff --git a/include/clang/Driver/Options.td b/include/clang/Driver/Options.td
index 08af5ad20a..957483c318 100644
--- a/include/clang/Driver/Options.td
+++ b/include/clang/Driver/Options.td
@@ -2025,6 +2025,8 @@ 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>,
diff --git a/lib/Basic/TargetInfo.cpp b/lib/Basic/TargetInfo.cpp
index 43ab77289b..a9dfe69b90 100644
--- a/lib/Basic/TargetInfo.cpp
+++ b/lib/Basic/TargetInfo.cpp
@@ -373,10 +373,15 @@ void TargetInfo::adjust(LangOptions &Opts) {
     LongDoubleFormat = &llvm::APFloat::IEEEquad();
   }
 
-  if (Opts.LongDoubleSize && Opts.LongDoubleSize == DoubleWidth) {
-    LongDoubleWidth = DoubleWidth;
-    LongDoubleAlign = DoubleAlign;
-    LongDoubleFormat = DoubleFormat;
+  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)
diff --git a/lib/Basic/Targets/PPC.cpp b/lib/Basic/Targets/PPC.cpp
index b052ef433e..bd0ae60038 100644
--- a/lib/Basic/Targets/PPC.cpp
+++ b/lib/Basic/Targets/PPC.cpp
@@ -465,6 +465,8 @@ 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 {
diff --git a/lib/Basic/Targets/X86.h b/lib/Basic/Targets/X86.h
index c0dfc81f57..588b6d3da1 100644
--- a/lib/Basic/Targets/X86.h
+++ b/lib/Basic/Targets/X86.h
@@ -133,6 +133,10 @@ public:
     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;
@@ -845,8 +849,6 @@ public:
       : LinuxTargetInfo<X86_64TargetInfo>(Triple, Opts) {
     LongDoubleFormat = &llvm::APFloat::IEEEquad();
   }
-
-  const char *getLongDoubleMangling() const override { return "g"; }
 };
 } // namespace targets
 } // namespace clang
diff --git a/lib/Driver/ToolChains/Clang.cpp b/lib/Driver/ToolChains/Clang.cpp
index 16360189f1..719123fdc3 100644
--- a/lib/Driver/ToolChains/Clang.cpp
+++ b/lib/Driver/ToolChains/Clang.cpp
@@ -4012,15 +4012,15 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
 
   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");
-    } else {
+        TC.getArch() == llvm::Triple::ppc || TC.getTriple().isPPC64())
+      A->render(Args, CmdArgs);
+    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
diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index 0d9e29da26..7a07d9955f 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -2742,7 +2742,9 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
   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);
diff --git a/test/CodeGen/ppc64-long-double.cpp b/test/CodeGen/ppc64-long-double.cpp
index 56cb24a3d1..d588d6b80e 100644
--- a/test/CodeGen/ppc64-long-double.cpp
+++ b/test/CodeGen/ppc64-long-double.cpp
@@ -2,8 +2,11 @@
 // 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);
diff --git a/test/CodeGen/x86-long-double.cpp b/test/CodeGen/x86-long-double.cpp
index a05470aeab..40ac29715f 100644
--- a/test/CodeGen/x86-long-double.cpp
+++ b/test/CodeGen/x86-long-double.cpp
@@ -16,6 +16,15 @@
 // 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
@@ -37,7 +46,11 @@ int size = sizeof(x);
 // 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)
diff --git a/test/Driver/mlong-double-128.c b/test/Driver/mlong-double-128.c
new file mode 100644
index 0000000000..ae76265a3b
--- /dev/null
+++ b/test/Driver/mlong-double-128.c
@@ -0,0 +1,11 @@
+// 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'