Revert part of a fix from 2010, changes since then:

a) x86-64 TLS has been documented
b) the code path should use movq for the correct relocation
   to be generated.

I've also added a fixme for the test case that we should improve
the code generated, it should look something like is documented
in the tls abi document.

llvm-svn: 192631

2 files changed, 6 insertions, 2 deletions

diff --git a/llvm/lib/Target/X86/X86InstrCompiler.td b/llvm/lib/Target/X86/X86InstrCompiler.td
index f62d68ce293..9e1cdc90571 100644
--- a/llvm/lib/Target/X86/X86InstrCompiler.td
+++ b/llvm/lib/Target/X86/X86InstrCompiler.td
@@ -969,7 +969,7 @@ def : Pat<(store (i64 (X86Wrapper tblockaddress:$src)), addr:$dst),
 // tls has some funny stuff here...
 // This corresponds to movabs $foo@tpoff, %rax
 def : Pat<(i64 (X86Wrapper tglobaltlsaddr :$dst)),
-          (MOV64ri tglobaltlsaddr :$dst)>;
+          (MOV64ri32 tglobaltlsaddr :$dst)>;
 // This corresponds to add $foo@tpoff, %rax
 def : Pat<(add GR64:$src1, (X86Wrapper tglobaltlsaddr :$dst)),
           (ADD64ri32 GR64:$src1, tglobaltlsaddr :$dst)>;
diff --git a/llvm/test/CodeGen/X86/x86-64-tls-1.ll b/llvm/test/CodeGen/X86/x86-64-tls-1.ll
index 8d3b300da3b..fee712d30b6 100644
--- a/llvm/test/CodeGen/X86/x86-64-tls-1.ll
+++ b/llvm/test/CodeGen/X86/x86-64-tls-1.ll
@@ -1,6 +1,10 @@
 ; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu | FileCheck %s
 @tm_nest_level = internal thread_local global i32 0
 define i64 @z() nounwind {
-; CHECK: movabsq    $tm_nest_level@TPOFF, %rcx
+; FIXME: The codegen here is primative at best and could be much better.
+; The add and the moves can be folded together.
+; CHECK: movq    $tm_nest_level@TPOFF, %rcx
+; CHECK: movq    %fs:0, %rax
+; CHECK: addl    %ecx, %eax
   ret i64 and (i64 ptrtoint (i32* @tm_nest_level to i64), i64 100)
 }