Add external interface for creating a pass token
Currently it's impossible for external code to register a pass because
the only source file that can create pass tokens is optimizer.cpp. This
makes it hard to add passes that can't be upstreamed since you can't run
them from the usual pass sequence without reimplementing Optimizer.
This change adds a PassToken constructor that takes unique_ptr to
opt::Pass; if out-of-tree code implements opt::Pass it can register a
custom pass without having to add it to SPIRV-Tools source code.
diff --git a/include/spirv-tools/optimizer.hpp b/include/spirv-tools/optimizer.hpp
index 5ec0e6b..e1eeedf 100644
--- a/include/spirv-tools/optimizer.hpp
+++ b/include/spirv-tools/optimizer.hpp
@@ -25,6 +25,10 @@
namespace spvtools {
+namespace opt {
+class Pass;
+}
+
// C++ interface for SPIR-V optimization functionalities. It wraps the context
// (including target environment and the corresponding SPIR-V grammar) and
// provides methods for registering optimization passes and optimizing.
@@ -41,6 +45,12 @@
PassToken(std::unique_ptr<Impl>);
+ // Tokens for built-in passes should be created using Create*Pass functions
+ // below; for out-of-tree passes, use this constructor instead.
+ // Note that this API isn't guaranteed to be stable and may change without
+ // preserving source or binary compatibility in the future.
+ PassToken(std::unique_ptr<opt::Pass>&& pass);
+
// Tokens can only be moved. Copying is disabled.
PassToken(const PassToken&) = delete;
PassToken(PassToken&&);