[CIR] cir.call with scalar return type (#135552)

This PR introduces support for calling functions with a scalar return
type to the upstream. This PR also includes an initial version of
`CIRGenTargetInfo` and related definitions which are essential for the
CIRGen of call ops.

Related to #132487 .

1 files changed, 28 insertions, 0 deletions

diff --git a/clang/lib/CIR/CodeGen/CIRGenModule.cpp b/clang/lib/CIR/CodeGen/CIRGenModule.cpp
index ddcdc0d..1b50454 100644
--- a/clang/lib/CIR/CodeGen/CIRGenModule.cpp
+++ b/clang/lib/CIR/CodeGen/CIRGenModule.cpp
@@ -129,6 +129,34 @@ CharUnits CIRGenModule::getNaturalTypeAlignment(QualType t,
   return alignment;
 }
 
+const TargetCIRGenInfo &CIRGenModule::getTargetCIRGenInfo() {
+  if (theTargetCIRGenInfo)
+    return *theTargetCIRGenInfo;
+
+  const llvm::Triple &triple = getTarget().getTriple();
+  switch (triple.getArch()) {
+  default:
+    assert(!cir::MissingFeatures::targetCIRGenInfoArch());
+
+    // Currently we just fall through to x86_64.
+    [[fallthrough]];
+
+  case llvm::Triple::x86_64: {
+    switch (triple.getOS()) {
+    default:
+      assert(!cir::MissingFeatures::targetCIRGenInfoOS());
+
+      // Currently we just fall through to x86_64.
+      [[fallthrough]];
+
+    case llvm::Triple::Linux:
+      theTargetCIRGenInfo = createX8664TargetCIRGenInfo(genTypes);
+      return *theTargetCIRGenInfo;
+    }
+  }
+  }
+}
+
 mlir::Location CIRGenModule::getLoc(SourceLocation cLoc) {
   assert(cLoc.isValid() && "expected valid source location");
   const SourceManager &sm = astContext.getSourceManager();