[OpenCL] Add builtin header test

Add a test to verify OpenCL builtin declarations using
OpenCLBuiltins.td.

This test consists of parsing a 60k line generated input file.  The
entire test takes about 60s with a debug build on a decent machine.
Admittedly this is not the fastest test, but doesn't seem excessive
compared to other tests in clang/test/Headers (with one of the tests
taking 85s for example).

RFC: https://lists.llvm.org/pipermail/cfe-dev/2021-April/067973.html

Differential Revision: https://reviews.llvm.org/D97869

diff --git a/clang/test/Headers/lit.local.cfg b/clang/test/Headers/lit.local.cfg
new file mode 100644 (file)
index 0000000..7774a20
--- /dev/null
+++ b/clang/test/Headers/lit.local.cfg
@@ -0,0 +1,4 @@
+config.substitutions = list(config.substitutions)
+
+# Enable substituting Clang Sema source directory for TableGen input.
+config.substitutions.append(('%clang_src_sema_dir', os.path.join(config.clang_src_dir, 'lib', 'Sema')))

diff --git a/clang/test/Headers/opencl-builtins.cl b/clang/test/Headers/opencl-builtins.cl
new file mode 100644 (file)
index 0000000..68ac292
--- /dev/null
+++ b/clang/test/Headers/opencl-builtins.cl
@@ -0,0 +1,19 @@
+// RUN: clang-tblgen -gen-clang-opencl-builtin-tests %clang_src_sema_dir/OpenCLBuiltins.td -o %t.cl
+// RUN: %clang_cc1 -include %s %t.cl -triple spir -verify -fsyntax-only -cl-std=CL2.0 -finclude-default-header
+// RUN: %clang_cc1 -include %s %t.cl -triple spir -verify -fsyntax-only -cl-std=CL2.0 -fdeclare-opencl-builtins -finclude-default-header
+
+// Generate an OpenCL source file containing a call to each builtin from
+// OpenCLBuiltins.td and then run that generated source file through the
+// frontend.
+//
+// Then test that:
+//  - The generated file can be parsed using opencl-c.h, giving some confidence
+//    that OpenCLBuiltins.td does not provide more than what opencl-c.h provides
+//    (but not vice versa).
+//
+//  - The generated file can be parsed using -fdeclare-opencl-builtins, ensuring
+//    some internal consistency of declarations in OpenCLBuiltins.td.  For
+//    example, addition of builtin declarations that lead to ambiguity during
+//    overload resolution will cause this test to fail.
+
+// expected-no-diagnostics