[llvm] 01353d8 - [llvm-jitlink] Allow -entry option to find hidden symbols.

[Lang Hames via llvm-commits]

Author: Lang Hames
Date: 2021-12-05T16:26:21+11:00
New Revision: 01353d81ea607c587d00d905a12dcddd8f34548e

URL: https://github.com/llvm/llvm-project/commit/01353d81ea607c587d00d905a12dcddd8f34548e
DIFF: https://github.com/llvm/llvm-project/commit/01353d81ea607c587d00d905a12dcddd8f34548e.diff

LOG: [llvm-jitlink] Allow -entry option to find hidden symbols.

This is useful when debugging failures in object files compiled with
visibility=hidden.

Added: 
    

Modified: 
    llvm/tools/llvm-jitlink/llvm-jitlink.cpp
    llvm/tools/llvm-jitlink/llvm-jitlink.h

Removed: 
    


################################################################################
diff  --git a/llvm/tools/llvm-jitlink/llvm-jitlink.cpp b/llvm/tools/llvm-jitlink/llvm-jitlink.cpp
index 202b459a6078f..b643a8f0f76d6 100644
--- a/llvm/tools/llvm-jitlink/llvm-jitlink.cpp
+++ b/llvm/tools/llvm-jitlink/llvm-jitlink.cpp
@@ -1301,7 +1301,7 @@ static Error loadObjects(Session &S) {
   {
     // Create a "main" JITLinkDylib.
     IdxToJLD[0] = S.MainJD;
-    S.JDSearchOrder.push_back(S.MainJD);
+    S.JDSearchOrder.push_back({S.MainJD, JITDylibLookupFlags::MatchAllSymbols});
     LLVM_DEBUG(dbgs() << "  0: " << S.MainJD->getName() << "\n");
 
     // Add any extra JITLinkDylibs from the command line.
@@ -1314,15 +1314,18 @@ static Error loadObjects(Session &S) {
       unsigned JDIdx =
           JITLinkDylibs.getPosition(JLDItr - JITLinkDylibs.begin());
       IdxToJLD[JDIdx] = &*JD;
-      S.JDSearchOrder.push_back(&*JD);
+      S.JDSearchOrder.push_back({&*JD, JITDylibLookupFlags::MatchAllSymbols});
       LLVM_DEBUG(dbgs() << "  " << JDIdx << ": " << JD->getName() << "\n");
     }
 
-    // Set every dylib to link against every other, in command line order.
-    for (auto *JD : S.JDSearchOrder) {
+    // Set every dylib to link against every other, in command line order,
+    // using exported symbols only.
+    for (auto &KV : S.JDSearchOrder) {
+      auto *JD = KV.first;
       auto LookupFlags = JITDylibLookupFlags::MatchExportedSymbolsOnly;
       JITDylibSearchOrder LinkOrder;
-      for (auto *JD2 : S.JDSearchOrder) {
+      for (auto &KV2 : S.JDSearchOrder) {
+        auto *JD2 = KV2.first;
         if (JD2 == JD)
           continue;
         LinkOrder.push_back(std::make_pair(JD2, LookupFlags));
@@ -1395,8 +1398,8 @@ static Error loadObjects(Session &S) {
 
   LLVM_DEBUG({
     dbgs() << "Dylib search order is [ ";
-    for (auto *JD : S.JDSearchOrder)
-      dbgs() << JD->getName() << " ";
+    for (auto &KV : S.JDSearchOrder)
+      dbgs() << KV.first->getName() << " ";
     dbgs() << "]\n";
   });
 
@@ -1553,7 +1556,7 @@ static void dumpSessionStats(Session &S) {
 }
 
 static Expected<JITEvaluatedSymbol> getMainEntryPoint(Session &S) {
-  return S.ES.lookup(S.JDSearchOrder, EntryPointName);
+  return S.ES.lookup(S.JDSearchOrder, S.ES.intern(EntryPointName));
 }
 
 static Expected<JITEvaluatedSymbol> getOrcRuntimeEntryPoint(Session &S) {
@@ -1561,7 +1564,7 @@ static Expected<JITEvaluatedSymbol> getOrcRuntimeEntryPoint(Session &S) {
   const auto &TT = S.ES.getExecutorProcessControl().getTargetTriple();
   if (TT.getObjectFormat() == Triple::MachO)
     RuntimeEntryPoint = '_' + RuntimeEntryPoint;
-  return S.ES.lookup(S.JDSearchOrder, RuntimeEntryPoint);
+  return S.ES.lookup(S.JDSearchOrder, S.ES.intern(RuntimeEntryPoint));
 }
 
 static Expected<int> runWithRuntime(Session &S, ExecutorAddr EntryPointAddr) {
@@ -1630,11 +1633,20 @@ int main(int argc, char *argv[]) {
     // Find the entry-point function unconditionally, since we want to force
     // it to be materialized to collect stats.
     EntryPoint = ExitOnErr(getMainEntryPoint(*S));
+    LLVM_DEBUG({
+      dbgs() << "Using entry point \"" << EntryPointName
+             << "\": " << formatv("{0:x16}", EntryPoint.getAddress()) << "\n";
+    });
 
     // If we're running with the ORC runtime then replace the entry-point
     // with the __orc_rt_run_program symbol.
-    if (!OrcRuntime.empty())
+    if (!OrcRuntime.empty()) {
       EntryPoint = ExitOnErr(getOrcRuntimeEntryPoint(*S));
+      LLVM_DEBUG({
+        dbgs() << "(called via __orc_rt_run_program_wrapper at "
+               << formatv("{0:x16}", EntryPoint.getAddress()) << ")\n";
+      });
+    }
   }
 
   if (ShowAddrs)

diff  --git a/llvm/tools/llvm-jitlink/llvm-jitlink.h b/llvm/tools/llvm-jitlink/llvm-jitlink.h
index ecf370959385d..7d58cd4ac62f1 100644
--- a/llvm/tools/llvm-jitlink/llvm-jitlink.h
+++ b/llvm/tools/llvm-jitlink/llvm-jitlink.h
@@ -50,7 +50,7 @@ struct Session {
   orc::ExecutionSession ES;
   orc::JITDylib *MainJD = nullptr;
   LLVMJITLinkObjectLinkingLayer ObjLayer;
-  std::vector<orc::JITDylib *> JDSearchOrder;
+  orc::JITDylibSearchOrder JDSearchOrder;
 
   ~Session();