From 35ed842773da41779d57d3ed23f440202d0be198 Mon Sep 17 00:00:00 2001
From: Jim Grosbach <grosbach@apple.com>
Date: Wed, 5 Sep 2012 16:50:40 +0000
Subject: [PATCH] MCJIT: getPointerToFunction() references target address
 space.

Make sure to return a pointer into the target memory, not the local memory.
Often they are the same, but we can't assume that.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163217 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/ExecutionEngine/RuntimeDyld.h        |  4 ++++
 lib/ExecutionEngine/MCJIT/MCJIT.cpp               | 12 ++++++++++--
 lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp   |  4 ++++
 lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h | 13 +++++++++++++
 4 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/include/llvm/ExecutionEngine/RuntimeDyld.h b/include/llvm/ExecutionEngine/RuntimeDyld.h
index a5c9272d3ca..9e5ad2feb0d 100644
--- a/include/llvm/ExecutionEngine/RuntimeDyld.h
+++ b/include/llvm/ExecutionEngine/RuntimeDyld.h
@@ -73,6 +73,10 @@ public:
   /// and resolve relocatons based on where they put it).
   void *getSymbolAddress(StringRef Name);
 
+  /// Get the address of the target copy of the symbol. This is the address
+  /// used for relocation.
+  uint64_t getSymbolLoadAddress(StringRef Name);
+
   /// Resolve the relocations for all symbols we currently know about.
   void resolveRelocations();
 
diff --git a/lib/ExecutionEngine/MCJIT/MCJIT.cpp b/lib/ExecutionEngine/MCJIT/MCJIT.cpp
index 99c65ecf950..fa71305145e 100644
--- a/lib/ExecutionEngine/MCJIT/MCJIT.cpp
+++ b/lib/ExecutionEngine/MCJIT/MCJIT.cpp
@@ -113,6 +113,11 @@ void *MCJIT::getPointerToBasicBlock(BasicBlock *BB) {
 }
 
 void *MCJIT::getPointerToFunction(Function *F) {
+  // FIXME: This should really return a uint64_t since it's a pointer in the
+  // target address space, not our local address space. That's part of the
+  // ExecutionEngine interface, though. Fix that when the old JIT finally
+  // dies.
+
   // FIXME: Add support for per-module compilation state
   if (!isCompiled)
     emitObject(M);
@@ -126,10 +131,13 @@ void *MCJIT::getPointerToFunction(Function *F) {
 
   // FIXME: Should the Dyld be retaining module information? Probably not.
   // FIXME: Should we be using the mangler for this? Probably.
+  //
+  // This is the accessor for the target address, so make sure to check the
+  // load address of the symbol, not the local address.
   StringRef BaseName = F->getName();
   if (BaseName[0] == '\1')
-    return (void*)Dyld.getSymbolAddress(BaseName.substr(1));
-  return (void*)Dyld.getSymbolAddress((TM->getMCAsmInfo()->getGlobalPrefix()
+    return (void*)Dyld.getSymbolLoadAddress(BaseName.substr(1));
+  return (void*)Dyld.getSymbolLoadAddress((TM->getMCAsmInfo()->getGlobalPrefix()
                                        + BaseName).str());
 }
 
diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
index a98ddc0e12c..d47287b8781 100644
--- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
+++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
@@ -479,6 +479,10 @@ void *RuntimeDyld::getSymbolAddress(StringRef Name) {
   return Dyld->getSymbolAddress(Name);
 }
 
+uint64_t RuntimeDyld::getSymbolLoadAddress(StringRef Name) {
+  return Dyld->getSymbolLoadAddress(Name);
+}
+
 void RuntimeDyld::resolveRelocations() {
   Dyld->resolveRelocations();
 }
diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h
index 4b998eacfe3..d5df732b91c 100644
--- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h
+++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h
@@ -177,6 +177,10 @@ protected:
     return true;
   }
 
+  uint64_t getSectionLoadAddress(unsigned SectionID) {
+    return Sections[SectionID].LoadAddress;
+  }
+
   uint8_t *getSectionAddress(unsigned SectionID) {
     return (uint8_t*)Sections[SectionID].Address;
   }
@@ -270,6 +274,15 @@ public:
     return getSectionAddress(Loc.first) + Loc.second;
   }
 
+  uint64_t getSymbolLoadAddress(StringRef Name) {
+    // FIXME: Just look up as a function for now. Overly simple of course.
+    // Work in progress.
+    if (GlobalSymbolTable.find(Name) == GlobalSymbolTable.end())
+      return 0;
+    SymbolLoc Loc = GlobalSymbolTable.lookup(Name);
+    return getSectionLoadAddress(Loc.first) + Loc.second;
+  }
+
   void resolveRelocations();
 
   void reassignSectionAddress(unsigned SectionID, uint64_t Addr);
-- 
2.34.1