[CIR] Upstream cir-canonicalize pass (#131891)

This change introduces the cir-canonicalize pass. This is a simple
cir-to-cir transformation that eliminates empty scopes and redundant
branches. It will be expanded in future changes to simplify other
redundant instruction sequences.

MLIR verification and mlir-specific command-line option handling is also
introduced here.

1 files changed, 8 insertions, 0 deletions

diff --git a/clang/lib/CIR/CodeGen/CIRGenModule.cpp b/clang/lib/CIR/CodeGen/CIRGenModule.cpp
index 0e3e15c..36bfc2c 100644
--- a/clang/lib/CIR/CodeGen/CIRGenModule.cpp
+++ b/clang/lib/CIR/CodeGen/CIRGenModule.cpp
@@ -23,6 +23,7 @@
 #include "mlir/IR/BuiltinOps.h"
 #include "mlir/IR/Location.h"
 #include "mlir/IR/MLIRContext.h"
+#include "mlir/IR/Verifier.h"
 
 using namespace clang;
 using namespace clang::CIRGen;
@@ -488,6 +489,13 @@ mlir::Type CIRGenModule::convertType(QualType type) {
   return genTypes.convertType(type);
 }
 
+bool CIRGenModule::verifyModule() const {
+  // Verify the module after we have finished constructing it, this will
+  // check the structural properties of the IR and invoke any specific
+  // verifiers we have on the CIR operations.
+  return mlir::verify(theModule).succeeded();
+}
+
 DiagnosticBuilder CIRGenModule::errorNYI(SourceLocation loc,
                                          llvm::StringRef feature) {
   unsigned diagID = diags.getCustomDiagID(