[tvm] branch main updated: [Hexagon] Make local symbols visible to loaded modules in RPC server (#11611)

[kparzysz]

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kparzysz pushed a commit to branch main
in repository https://gitbox.apache.org/repos/asf/tvm.git


The following commit(s) were added to refs/heads/main by this push:
     new b00b1229c8 [Hexagon] Make local symbols visible to loaded modules in 
RPC server (#11611)
b00b1229c8 is described below

commit b00b1229c881fa6f2f9fe9e44819c9dc3de09f74
Author: Krzysztof Parzyszek <kparz...@quicinc.com>
AuthorDate: Wed Jun 8 07:24:36 2022 -0500

    [Hexagon] Make local symbols visible to loaded modules in RPC server 
(#11611)
    
    The simulator library `libhexagon_rpc_sim.so` contains TVM runtime built
    into it, but since it's loaded as a "local" library these symbols are not
    visible to shared libraries loaded by subsequent dlopens. (Same applies to
    symbols from the C++ runtime.)
    
    To make these symbols visible, dlopen the defining libraries as "global".
    (Re-dlopeninig an already loaded library is a well-defined operation.)
---
 src/runtime/hexagon/rpc/simulator/rpc_server.cc | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/src/runtime/hexagon/rpc/simulator/rpc_server.cc 
b/src/runtime/hexagon/rpc/simulator/rpc_server.cc
index 29373be542..9b4ce3f114 100644
--- a/src/runtime/hexagon/rpc/simulator/rpc_server.cc
+++ b/src/runtime/hexagon/rpc/simulator/rpc_server.cc
@@ -18,6 +18,7 @@
  */
 
 #include <HAP_farf.h>
+#include <dlfcn.h>
 
 #include <algorithm>
 #include <cassert>
@@ -288,7 +289,16 @@ int DISPATCH_FUNCTION_NAME(void* serverp) {
   return 0;
 }
 
-int main() {
+int main(int argc, char* argv[]) {
+  // Load C++RT and ourselves as "global" to make all the symbols defined
+  // there be visible to any subsequent libraries loaded via dlopen.
+  void* cxx_abi = dlopen("libc++abi.so", RTLD_GLOBAL);
+  ICHECK(cxx_abi != nullptr);
+  void* cxx = dlopen("libc++.so", RTLD_GLOBAL);
+  ICHECK(cxx != nullptr);
+  void* self = dlopen(argv[0], RTLD_GLOBAL);
+  ICHECK(self != nullptr);
+
   const auto* api = tvm::runtime::Registry::Get("device_api.hexagon");
   ICHECK(api != nullptr);
   tvm::runtime::Registry::Register("device_api.cpu", true).set_body(*api);
@@ -308,6 +318,9 @@ int main() {
     // nothing
   }
 
+  dlclose(self);
+  dlclose(cxx);
+  dlclose(cxx_abi);
   return 0;
 }