Enable support for __float128 in Clang and enable it on pertinent platforms

This patch corresponds to reviews:
http://reviews.llvm.org/D15120
http://reviews.llvm.org/D19125

It adds support for the __float128 keyword, literals and target feature to
enable it. Based on the latter of the two aforementioned reviews, this feature
is enabled on Linux on i386/X86 as well as SystemZ.
This is also the second attempt in commiting this feature. The first attempt
did not enable it on required platforms which caused failures when compiling
type_traits with -std=gnu++11.

If you see failures with compiling this header on your platform after this
commit, it is likely that your platform needs to have this feature enabled.

llvm-svn: 268898

1 files changed, 36 insertions, 0 deletions

diff --git a/clang/test/Sema/float128-ld-incompatibility.cpp b/clang/test/Sema/float128-ld-incompatibility.cpp
new file mode 100644
index 00000000000..d993ed7b081
--- /dev/null
+++ b/clang/test/Sema/float128-ld-incompatibility.cpp
@@ -0,0 +1,36 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 \
+// RUN: -triple powerpc64le-unknown-linux-gnu -target-cpu pwr8 \
+// RUN: -target-feature +float128 %s
+
+__float128 qf();
+long double ldf();
+
+// FIXME: once operations between long double and __float128 are implemented for
+//        targets where the types are different, these next two will change
+long double ld{qf()}; // expected-error {{cannot initialize a variable of type 'long double' with an rvalue of type '__float128'}}
+__float128 q{ldf()};  // expected-error {{cannot initialize a variable of type '__float128' with an rvalue of type 'long double'}}
+
+auto test1(__float128 q, long double ld) -> decltype(q + ld) { // expected-error {{invalid operands to binary expression ('__float128' and 'long double')}}
+  return q + ld;      // expected-error {{invalid operands to binary expression ('__float128' and 'long double')}}
+}
+
+auto test2(long double a, __float128 b) -> decltype(a + b) { // expected-error {{invalid operands to binary expression ('long double' and '__float128')}}
+  return a + b;      // expected-error {{invalid operands to binary expression ('long double' and '__float128')}}
+}
+
+void test3(bool b) {
+  long double ld;
+  __float128 q;
+
+  ld + q; // expected-error {{invalid operands to binary expression ('long double' and '__float128')}}
+  q + ld; // expected-error {{invalid operands to binary expression ('__float128' and 'long double')}}
+  ld - q; // expected-error {{invalid operands to binary expression ('long double' and '__float128')}}
+  q - ld; // expected-error {{invalid operands to binary expression ('__float128' and 'long double')}}
+  ld * q; // expected-error {{invalid operands to binary expression ('long double' and '__float128')}}
+  q * ld; // expected-error {{invalid operands to binary expression ('__float128' and 'long double')}}
+  ld / q; // expected-error {{invalid operands to binary expression ('long double' and '__float128')}}
+  q / ld; // expected-error {{invalid operands to binary expression ('__float128' and 'long double')}}
+  ld = q; // expected-error {{assigning to 'long double' from incompatible type '__float128'}}
+  q = ld; // expected-error {{assigning to '__float128' from incompatible type 'long double'}}
+  q + b ? q : ld; // expected-error {{incompatible operand types ('__float128' and 'long double')}}
+}