From 51a0437b166b612a89ad8f772c1f5538e8d52422 Mon Sep 17 00:00:00 2001
From: Nate Begeman <natebegeman@mac.com>
Date: Mon, 26 Jan 2009 01:24:32 +0000
Subject: [PATCH] Map address space 256 to gs; similar mappings could be
 supported for the other x86 segments.  address space 0 is stack/default,
 1-255 are reserved for client use.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62980 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/X86/X86Instr64bit.td |  5 +++++
 lib/Target/X86/X86InstrInfo.td  | 15 +++++++++++++++
 test/CodeGen/X86/movgs.ll       |  8 ++++++++
 3 files changed, 28 insertions(+)
 create mode 100644 test/CodeGen/X86/movgs.ll

diff --git a/lib/Target/X86/X86Instr64bit.td b/lib/Target/X86/X86Instr64bit.td
index 123062c6d05..774da61ba94 100644
--- a/lib/Target/X86/X86Instr64bit.td
+++ b/lib/Target/X86/X86Instr64bit.td
@@ -1242,6 +1242,11 @@ def TLS_addr64 : I<0, Pseudo, (outs GR64:$dst), (ins i64imm:$sym),
               ".byte\t0x66; leaq\t${sym:mem}(%rip), $dst; .word\t0x6666; rex64",
                   [(set GR64:$dst, (X86tlsaddr tglobaltlsaddr:$sym))]>;
 
+let AddedComplexity = 5 in
+def MOV64GSrm : RI<0x8B, MRMSrcMem, (outs GR64:$dst), (ins i64mem:$src),
+                 "movq\t%gs:$src, $dst",
+                 [(set GR64:$dst, (gsload addr:$src))]>, SegGS;
+
 //===----------------------------------------------------------------------===//
 // Atomic Instructions
 //===----------------------------------------------------------------------===//
diff --git a/lib/Target/X86/X86InstrInfo.td b/lib/Target/X86/X86InstrInfo.td
index fbe03299e07..9649c234de4 100644
--- a/lib/Target/X86/X86InstrInfo.td
+++ b/lib/Target/X86/X86InstrInfo.td
@@ -308,6 +308,16 @@ def nvloadi32 : PatFrag<(ops node:$ptr), (i32 (unindexedload node:$ptr)), [{
   return false;
 }]>;
 
+def gsload : PatFrag<(ops node:$ptr), (load node:$ptr), [{
+  LoadSDNode *LD = cast<LoadSDNode>(N);
+  const Value *Src = LD->getSrcValue();
+  if (!Src)
+    return false;
+  if (const PointerType *PT = dyn_cast<PointerType>(Src->getType()))
+    return PT->getAddressSpace() == 256;
+  return false;
+}]>;
+
 def loadi8  : PatFrag<(ops node:$ptr), (i8  (load node:$ptr))>;
 def loadi64 : PatFrag<(ops node:$ptr), (i64 (load node:$ptr))>;
 
@@ -2852,6 +2862,11 @@ def TLS_tp : I<0x8B, Pseudo, (outs GR32:$dst), (ins),
                "movl\t%gs:0, $dst",
                [(set GR32:$dst, X86TLStp)]>, SegGS;
 
+let AddedComplexity = 5 in
+def GS_MOV32rm : I<0x8B, MRMSrcMem, (outs GR32:$dst), (ins i32mem:$src),
+                   "movl\t%gs:$src, $dst",
+                   [(set GR32:$dst, (gsload addr:$src))]>, SegGS;
+
 //===----------------------------------------------------------------------===//
 // DWARF Pseudo Instructions
 //
diff --git a/test/CodeGen/X86/movgs.ll b/test/CodeGen/X86/movgs.ll
new file mode 100644
index 00000000000..f621849e5b0
--- /dev/null
+++ b/test/CodeGen/X86/movgs.ll
@@ -0,0 +1,8 @@
+; RUN: llvm-as < %s | llc -march=x86 | grep gs
+
+define i32 @foo() nounwind readonly {
+entry:
+	%tmp = load i32* addrspace(256)* getelementptr (i32* addrspace(256)* inttoptr (i32 72 to i32* addrspace(256)*), i32 31)		; <i32*> [#uses=1]
+	%tmp1 = load i32* %tmp		; <i32> [#uses=1]
+	ret i32 %tmp1
+}