Support for allocation of TLS variables in the JIT. Allocation of a global

variable is moved to the execution engine. The JIT calls the TargetJITInfo
to allocate thread local storage. Currently, only linux/x86 knows how to
allocate thread local global variables.

llvm-svn: 58142

2 files changed, 20 insertions, 1 deletions

diff --git a/llvm/lib/Target/X86/X86JITInfo.cpp b/llvm/lib/Target/X86/X86JITInfo.cpp
index 7b3a0703277..f8761dc87e2 100644
--- a/llvm/lib/Target/X86/X86JITInfo.cpp
+++ b/llvm/lib/Target/X86/X86JITInfo.cpp
@@ -518,3 +518,13 @@ void X86JITInfo::relocate(void *Function, MachineRelocation *MR,
     }
   }
 }
+
+char* X86JITInfo::allocateThreadLocalMemory(size_t size) {
+#if defined(X86_32_JIT) && !defined(__APPLE__) && !defined(_MSC_VER)
+  TLSOffset -= size;
+  return TLSOffset;
+#else
+  assert(0 && "Cannot allocate thread local storage on this arch!\n");
+  return 0;
+#endif
+}
diff --git a/llvm/lib/Target/X86/X86JITInfo.h b/llvm/lib/Target/X86/X86JITInfo.h
index f9fcefecff5..6b8d197846b 100644
--- a/llvm/lib/Target/X86/X86JITInfo.h
+++ b/llvm/lib/Target/X86/X86JITInfo.h
@@ -23,8 +23,12 @@ namespace llvm {
   class X86JITInfo : public TargetJITInfo {
     X86TargetMachine &TM;
     intptr_t PICBase;
+    char* TLSOffset;
   public:
-    explicit X86JITInfo(X86TargetMachine &tm) : TM(tm) {useGOT = 0;}
+    explicit X86JITInfo(X86TargetMachine &tm) : TM(tm) {
+      useGOT = 0;
+      TLSOffset = 0;
+    }
 
     /// replaceMachineCodeForFunction - Make it so that calling the function
     /// whose machine code is at OLD turns into a call to NEW, perhaps by
@@ -56,6 +60,11 @@ namespace llvm {
     /// referenced global symbols.
     virtual void relocate(void *Function, MachineRelocation *MR,
                           unsigned NumRelocs, unsigned char* GOTBase);
+    
+    /// allocateThreadLocalMemory - Each target has its own way of
+    /// handling thread local variables. This method returns a value only
+    /// meaningful to the target.
+    virtual char* allocateThreadLocalMemory(size_t size);
 
     /// setPICBase / getPICBase - Getter / setter of PICBase, used to compute
     /// PIC jumptable entry.