[X86] Don't try to generate direct calls to TLS globals

The call lowering assumes that if the callee is a global, we want to emit a direct call.
This is correct for regular globals, but not for TLS ones.

Differential Revision: http://reviews.llvm.org/D6862

llvm-svn: 225438

2 files changed, 21 insertions, 1 deletions

diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index 29321472e25..9555dec9b89 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -3083,10 +3083,11 @@ X86TargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
     // through a register, since the call instruction's 32-bit
     // pc-relative offset may not be large enough to hold the whole
     // address.
-  } else if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee)) {
+  } else if (Callee->getOpcode() == ISD::GlobalAddress) {
     // If the callee is a GlobalAddress node (quite common, every direct call
     // is) turn it into a TargetGlobalAddress node so that legalize doesn't hack
     // it.
+    GlobalAddressSDNode* G = cast<GlobalAddressSDNode>(Callee);
 
     // We should use extra load for direct calls to dllimported functions in
     // non-JIT mode.
diff --git a/llvm/test/CodeGen/X86/pr22103.ll b/llvm/test/CodeGen/X86/pr22103.ll
new file mode 100644
index 00000000000..324b6b562b8
--- /dev/null
+++ b/llvm/test/CodeGen/X86/pr22103.ll
@@ -0,0 +1,19 @@
+; RUN: llc < %s | FileCheck %s

+; Don't try to emit a direct call through a TLS global.

+; This fixes PR22103

+

+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"

+target triple = "x86_64-unknown-linux-gnu"

+

+@a = external thread_local global i64

+

+; Function Attrs: nounwind

+define void @_Z1fv() {

+; CHECK-NOT: callq *$a

+; CHECK: movq %fs:0, [[RAX:%r..]]

+; CHECK-NEXT: addq    a@GOTTPOFF(%rip), [[RAX]]

+; CHECK-NEXT: callq *%rax

+entry:

+  call void bitcast (i64* @a to void ()*)()

+  ret void

+}