Add support for Float16, Float32, Float64 and Float128

Upgrade libgccjit.version

Limit new Floatxx types to master branch only

apply rustfmt

Make new types available only when requested

Make new types available only when requested

Check if Float16 and Float128 are supported by the target platform

Author: Robert Zakrzewski

Cargo.lock

@@ -1 +1 @@
-b6f163f52
+ab469a6daaed9f4191ac8c32894b3f44d78b2ba5

libgccjit.version

@@ -1,4 +1,4 @@
-use gccjit::{RValue, Struct, Type};
+use gccjit::{CType, RValue, Struct, Type};
 use rustc_codegen_ssa::common::TypeKind;
 use rustc_codegen_ssa::traits::{BaseTypeMethods, DerivedTypeMethods, TypeMembershipMethods};
 use rustc_middle::ty::layout::TyAndLayout;
@@ -120,8 +120,17 @@ impl<'gcc, 'tcx> BaseTypeMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
         self.isize_type
     }
 
+    #[cfg(feature = "master")]
     fn type_f16(&self) -> Type<'gcc> {
-        unimplemented!("f16_f128")
+        if self.context.get_target_info().supports_target_dependent_type(CType::Float16) {
+            return self.context.new_c_type(CType::Float16);
+        }
+        unimplemented!("f16")
+    }
+
+    #[cfg(not(feature = "master"))]
+    fn type_f16(&self) -> Type<'gcc> {
+        unimplemented!("f16")
     }
 
     fn type_f32(&self) -> Type<'gcc> {
@@ -132,8 +141,17 @@ impl<'gcc, 'tcx> BaseTypeMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
         self.double_type
     }
 
+    #[cfg(feature = "master")]
+    fn type_f128(&self) -> Type<'gcc> {
+        if self.context.get_target_info().supports_target_dependent_type(CType::Float128) {
+            return self.context.new_c_type(CType::Float128);
+        }
+        unimplemented!("f128")
+    }
+
+    #[cfg(not(feature = "master"))]
     fn type_f128(&self) -> Type<'gcc> {
-        unimplemented!("f16_f128")
+        unimplemented!("f128")
     }
 
     fn type_func(&self, params: &[Type<'gcc>], return_type: Type<'gcc>) -> Type<'gcc> {