Add JL_REQUIRE_TPIN for arguments

Author: qinsoon

src/clangsa/GCChecker.cpp

@@ -201,8 +201,13 @@ class GCChecker
         VS.FD = FD;
         return VS;
       }
-      // Assume arguments are pinned
-      return getRooted(nullptr, ValueState::Pinned, -1);
+      bool require_tpin = declHasAnnotation(PVD, "julia_require_tpin");
+      if (require_tpin) {
+        return getRooted(nullptr, ValueState::TransitivelyPinned, -1);
+      } else {
+        // Assume arguments are pinned
+        return getRooted(nullptr, ValueState::Pinned, -1);
+      }      
     }
   };
 
@@ -884,7 +889,10 @@ void GCChecker::checkBeginFunction(CheckerContext &C) const {
       auto Param = State->getLValue(P, LCtx);
       const MemRegion *Root = State->getSVal(Param).getAsRegion();
       State = State->set<GCRootMap>(Root, RootState::getRoot(-1));
-      State = State->set<GCPinMap>(Root, PinState::getPin(-1));
+      if (declHasAnnotation(P, "julia_require_tpin"))
+        State = State->set<GCPinMap>(Root, PinState::getTransitivePin(-1));
+      else
+        State = State->set<GCPinMap>(Root, PinState::getTransitivePin(-1));
     } else if (isGCTrackedType(P->getType())) {
       auto Param = State->getLValue(P, LCtx);
       SymbolRef AssignedSym = State->getSVal(Param).getAsSymbol();
@@ -1631,6 +1639,11 @@ void GCChecker::checkPreCall(const CallEvent &Call, CheckerContext &C) const {
         report_value_error(C, Sym, "Passing non-pinned value as argument to function that may GC", range);
       }
     }
+    if (FD && idx < FD->getNumParams() && declHasAnnotation(FD->getParamDecl(idx), "julia_require_tpin")) {
+      if (!ValState->isTransitivelyPinned()) {
+        report_value_error(C, Sym, "Passing non-tpinned argument to function that requires a tpin argument.");
+      }
+    }
   }
 }
 

src/support/analyzer_annotations.h

@@ -23,6 +23,7 @@
 #define JL_ALWAYS_LEAFTYPE JL_GLOBALLY_ROOTED
 #define JL_ROOTS_TEMPORARILY __attribute__((annotate("julia_temporarily_roots")))
 #define JL_REQUIRE_ROOTED_SLOT __attribute__((annotate("julia_require_rooted_slot")))
+#define JL_REQUIRE_TPIN __attribute__((annotate("julia_require_tpin")))
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -52,6 +53,7 @@ extern "C" {
 #define JL_ALWAYS_LEAFTYPE
 #define JL_ROOTS_TEMPORARILY
 #define JL_REQUIRE_ROOTED_SLOT
+#define JL_REQUIRE_TPIN
 #define JL_GC_PROMISE_ROOTED(x) (void)(x)
 #define jl_may_leak(x) (void)(x)
 

test/clangsa/MissingPinning.c

@@ -179,3 +179,26 @@ void rebind_tpin_simple2() {
     look_at_value(v);
     JL_GC_POP();
 }
+
+int transitive_closure(jl_value_t *v JL_REQUIRE_TPIN) {
+    if (jl_is_unionall(v)) {
+        jl_unionall_t *ua = (jl_unionall_t*)v;
+        return transitive_closure(ua->body);
+    }
+    return 0;
+}
+
+extern void look_at_tpin_value(jl_value_t *v JL_REQUIRE_TPIN);
+
+int properly_tpin_arg(jl_value_t *v) {
+    JL_GC_PUSH1(&v);
+    look_at_tpin_value(v);
+    JL_GC_POP();
+}
+
+int no_tpin_arg(jl_value_t *v) {
+    look_at_tpin_value(v); // expected-warning{{Passing non-tpinned argument to function that requires a tpin argument}}
+                           // expected-note@-1{{Passing non-tpinned argument to function that requires a tpin argument}}
+                           // expected-note@+1{{Started tracking value here (root was inherited)}}
+}
+