[ORC] Add support for emulated TLS to ORCv2.

This commit adds a ManglingOptions struct to IRMaterializationUnit, and replaces
IRCompileLayer::CompileFunction with a new IRCompileLayer::IRCompiler class. The
ManglingOptions struct defines the emulated-TLS state (via a bool member,
EmulatedTLS, which is true if emulated-TLS is enabled and false otherwise). The
IRCompileLayer::IRCompiler class wraps an IRCompiler (the same way that the
CompileFunction typedef used to), but adds a method to return the
IRCompileLayer::ManglingOptions that the compiler will use.

These changes allow us to correctly determine the symbols that will be produced
when a thread local global variable defined at the IR level is compiled with or
without emulated TLS. This is required for ORCv2, where MaterializationUnits
must declare their interface up-front.

Most ORCv2 clients should not require any changes. Clients writing custom IR
compilers will need to wrap their compiler in an IRCompileLayer::IRCompiler,
rather than an IRCompileLayer::CompileFunction, however this should be a
straightforward change (see modifications to CompileUtils.* in this patch for an
example).

(cherry picked from commit ce2207abaf9a925b35f15ef92aaff6b301ba6d22)

1 files changed, 15 insertions, 6 deletions

diff --git a/llvm/tools/lli/lli.cpp b/llvm/tools/lli/lli.cpp
index bfe7e8f0430..0efd0df2c12 100644
--- a/llvm/tools/lli/lli.cpp
+++ b/llvm/tools/lli/lli.cpp
@@ -197,6 +197,11 @@ namespace {
     cl::desc("Generate software floating point library calls"),
     cl::init(false));
 
+  cl::opt<bool> NoProcessSymbols(
+      "no-process-syms",
+      cl::desc("Do not resolve lli process symbols in JIT'd code"),
+      cl::init(false));
+
   enum class DumpKind {
     NoDump,
     DumpFuncsToStdOut,
@@ -794,12 +799,16 @@ int runOrcLazyJIT(const char *ProgName) {
   });
 
   orc::MangleAndInterner Mangle(J->getExecutionSession(), J->getDataLayout());
-  J->getMainJITDylib().addGenerator(
-      ExitOnErr(orc::DynamicLibrarySearchGenerator::GetForCurrentProcess(
-          J->getDataLayout().getGlobalPrefix(),
-          [MainName = Mangle("main")](const orc::SymbolStringPtr &Name) {
-            return Name != MainName;
-          })));
+
+  // Unless they've been explicitly disabled, make process symbols available to
+  // JIT'd code.
+  if (!NoProcessSymbols)
+    J->getMainJITDylib().addGenerator(
+        ExitOnErr(orc::DynamicLibrarySearchGenerator::GetForCurrentProcess(
+            J->getDataLayout().getGlobalPrefix(),
+            [MainName = Mangle("main")](const orc::SymbolStringPtr &Name) {
+              return Name != MainName;
+            })));
 
   orc::LocalCXXRuntimeOverrides CXXRuntimeOverrides;
   ExitOnErr(CXXRuntimeOverrides.enable(J->getMainJITDylib(), Mangle));