Interface changes to allow RuntimeDyld memory managers to set memory permissions after an object has been loaded.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168114 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/ExecutionEngine/JIT/JITMemoryManager.cpp b/lib/ExecutionEngine/JIT/JITMemoryManager.cpp
index 61bc119..bd0519e 100644
--- a/lib/ExecutionEngine/JIT/JITMemoryManager.cpp
+++ b/lib/ExecutionEngine/JIT/JITMemoryManager.cpp
@@ -501,10 +501,14 @@
/// allocateDataSection - Allocate memory for a data section.
uint8_t *allocateDataSection(uintptr_t Size, unsigned Alignment,
- unsigned SectionID) {
+ unsigned SectionID, bool IsReadOnly) {
return (uint8_t*)DataAllocator.Allocate(Size, Alignment);
}
+ bool applyPermissions(std::string *ErrMsg) {
+ return false;
+ }
+
/// startExceptionTable - Use startFunctionBody to allocate memory for the
/// function's exception table.
uint8_t* startExceptionTable(const Function* F, uintptr_t &ActualSize) {
diff --git a/lib/ExecutionEngine/MCJIT/MCJIT.cpp b/lib/ExecutionEngine/MCJIT/MCJIT.cpp
index 752c5b7..d72e563 100644
--- a/lib/ExecutionEngine/MCJIT/MCJIT.cpp
+++ b/lib/ExecutionEngine/MCJIT/MCJIT.cpp
@@ -118,17 +118,26 @@
// FIXME: Add a parameter to identify which object is being finalized when
// MCJIT supports multiple modules.
+// FIXME: Provide a way to separate code emission, relocations and page
+// protection in the interface.
void MCJIT::finalizeObject() {
// If the module hasn't been compiled, just do that.
if (!isCompiled) {
// If the call to Dyld.resolveRelocations() is removed from emitObject()
// we'll need to do that here.
emitObject(M);
+
+ // Set page permissions.
+ MemMgr->applyPermissions();
+
return;
}
// Resolve any relocations.
Dyld.resolveRelocations();
+
+ // Set page permissions.
+ MemMgr->applyPermissions();
}
void *MCJIT::getPointerToBasicBlock(BasicBlock *BB) {
diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
index f6dccb1..4118e8a 100644
--- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
+++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
@@ -182,7 +182,7 @@
// Allocate memory for the section
unsigned SectionID = Sections.size();
uint8_t *Addr = MemMgr->allocateDataSection(TotalSize, sizeof(void*),
- SectionID);
+ SectionID, false);
if (!Addr)
report_fatal_error("Unable to allocate memory for common symbols!");
uint64_t Offset = 0;
@@ -237,11 +237,13 @@
bool IsRequired;
bool IsVirtual;
bool IsZeroInit;
+ bool IsReadOnly;
uint64_t DataSize;
StringRef Name;
Check(Section.isRequiredForExecution(IsRequired));
Check(Section.isVirtual(IsVirtual));
Check(Section.isZeroInit(IsZeroInit));
+ Check(Section.isReadOnlyData(IsReadOnly));
Check(Section.getSize(DataSize));
Check(Section.getName(Name));
@@ -256,7 +258,7 @@
Allocate = DataSize + StubBufSize;
Addr = IsCode
? MemMgr->allocateCodeSection(Allocate, Alignment, SectionID)
- : MemMgr->allocateDataSection(Allocate, Alignment, SectionID);
+ : MemMgr->allocateDataSection(Allocate, Alignment, SectionID, IsReadOnly);
if (!Addr)
report_fatal_error("Unable to allocate section memory!");
@@ -451,6 +453,12 @@
//===----------------------------------------------------------------------===//
// RuntimeDyld class implementation
RuntimeDyld::RuntimeDyld(RTDyldMemoryManager *mm) {
+ // FIXME: There's a potential issue lurking here if a single instance of
+ // RuntimeDyld is used to load multiple objects. The current implementation
+ // associates a single memory manager with a RuntimeDyld instance. Even
+ // though the public class spawns a new 'impl' instance for each load,
+ // they share a single memory manager. This can become a problem when page
+ // permissions are applied.
Dyld = 0;
MM = mm;
}