Index: lib/Target/X86/X86ISelDAGToDAG.cpp
===================================================================
--- lib/Target/X86/X86ISelDAGToDAG.cpp
+++ lib/Target/X86/X86ISelDAGToDAG.cpp
@@ -941,11 +941,12 @@
   bool IsRIPRel = N.getOpcode() == X86ISD::WrapperRIP;
 
   // Only do this address mode folding for 64-bit if we're in the small code
-  // model.
-  // FIXME: But we can do GOTPCREL addressing in the medium code model.
+  // model or medium code model.
   CodeModel::Model M = TM.getCodeModel();
-  if (Subtarget->is64Bit() && M != CodeModel::Small && M != CodeModel::Kernel)
-    return true;
+  if (Subtarget->is64Bit() && M != CodeModel::Small && M != CodeModel::Kernel
+      && !(M == CodeModel::Medium && IsRIPRel) ) {
+      return true;
+  }
 
   // Base and index reg must be 0 in order to use %rip as base.
   if (IsRIPRel && AM.hasBaseOrIndexReg())
Index: lib/Target/X86/X86ISelLowering.cpp
===================================================================
--- lib/Target/X86/X86ISelLowering.cpp
+++ lib/Target/X86/X86ISelLowering.cpp
@@ -4420,14 +4420,14 @@
   if (!hasSymbolicDisplacement)
     return true;
 
-  // FIXME: Some tweaks might be needed for medium code model.
-  if (M != CodeModel::Small && M != CodeModel::Kernel)
+  if (M != CodeModel::Small && M != CodeModel::Medium && M != CodeModel::Kernel)
     return false;
 
-  // For small code model we assume that latest object is 16MB before end of 31
-  // bits boundary. We may also accept pretty large negative constants knowing
-  // that all objects are in the positive half of address space.
-  if (M == CodeModel::Small && Offset < 16*1024*1024)
+  // For small and medium code model we assume that latest object is 16MB before
+  // end of 31 bits boundary. We may also accept pretty large negative constants
+  // knowing that all objects are in the positive half of address space.
+  if ((M == CodeModel::Small || M == CodeModel::Medium)
+      && Offset < 16*1024*1024)
     return true;
 
   // For kernel code model we know that all object resist in the negative half
@@ -15519,7 +15519,7 @@
 
   CodeModel::Model M = getTargetMachine().getCodeModel();
   if (Subtarget.isPICStyleRIPRel() &&
-      (M == CodeModel::Small || M == CodeModel::Kernel))
+      (M == CodeModel::Small || M == CodeModel::Medium || M == CodeModel::Kernel))
     return X86ISD::WrapperRIP;
 
   // GOTPCREL references must always use RIP.
Index: test/CodeGen/X86/x86-64-codemodel-medium-external.ll
===================================================================
--- /dev/null
+++ test/CodeGen/X86/x86-64-codemodel-medium-external.ll
@@ -0,0 +1,71 @@
+; RUN: llc < %s -code-model=medium -relocation-model=pic | FileCheck -check-prefix CHECK-MEDIUM-PIC %s
+; RUN: llc < %s -code-model=medium | FileCheck -check-prefix CHECK-MEDIUM %s
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+;This is to test the external global access under PIC/no-PIC medium code model
+;with different size and offset. This is to enusre the modification not break i
+;the other code path on handling the medium code model
+;
+;for medium code model,
+; Small symbols are also assumed to be linked into the low 2GB
+; Symbols with sizes larger than -mlarge-data-threshold
+;  are put into large data or bss sections and can be located above 2GB
+; Data is considered large when it's larger than large-data-threshold,
+;  which is 64KB by default
+; on PIC, both generate the same addressing mode
+
+@global_arr = external global [100 x i32], align 16
+@t = external global i32, align 4
+@global_arr_big = external global [50000 x i32], align 16
+
+@x1 = external global [8388608 x i32], align 16
+
+define i32 @f_offset_gt_16M() {
+entry:
+; CHECK-MEDIUM-PIC-LABEL: f_offset_gt_16M:
+; CHECK-MEDIUM-PIC:  movq    x1@GOTPCREL(%rip), %rax
+; CHECK-MEDIUM-PIC:  movl    20971520(%rax), %eax
+; CHECK-MEDIUM-LABEL:  f_offset_gt_16M:
+; CHECK-MEDIUM:  movabsq $x1, %rax
+; CHECK-MEDIUM:  movl    20971520(%rax), %eax
+  %0 = load i32, i32* getelementptr inbounds ([8388608 x i32], [8388608 x i32]* @x1, i64 0, i64 5242880), align 16
+  ret i32 %0
+}
+
+;This is for small data
+define i32 @foo() {
+entry:
+; CHECK-MEDIUM-PIC-LABEL:  foo:
+; CHECK-MEDIUM-PIC:  movq    global_arr@GOTPCREL(%rip),
+; CHECK-MEDIUM-LABEL:  foo:
+; CHECK-MEDIUM:  movabsq $global_arr+28,
+  %0 = load i32, i32* getelementptr inbounds ([100 x i32], [100 x i32]* @global_arr, i64 0, i64 7), align 4
+  %1 = load i32, i32* @t, align 4
+  %add = add nsw i32 %1, %0
+  store i32 %add, i32* @t, align 4
+  %2 = load i32, i32* @t, align 4
+  ret i32 %2
+}
+
+;This is for big data
+define i32 @main() {
+entry:
+; CHECK-MEDIUM-PIC-LABEL:  main:
+; CHECK-MEDIUM-PIC:  movq    global_arr_big@GOTPCREL(%rip),
+; CHECK-MEDIUM-LABEL:  main:
+; CHECK-MEDIUM:  movabsq $global_arr_big+28,
+  %retval = alloca i32, align 4
+  store i32 0, i32* %retval, align 4
+  %call = call i32 @foo()
+  %0 = load i32, i32* @t, align 4
+  %add = add nsw i32 %0, %call
+  store i32 %add, i32* @t, align 4
+  %1 = load i32, i32* getelementptr inbounds ([50000 x i32], [50000 x i32]* @global_arr_big, i64 0, i64 7), align 4
+  %2 = load i32, i32* @t, align 4
+  %add1 = add nsw i32 %2, %1
+  store i32 %add1, i32* @t, align 4
+  %3 = load i32, i32* @t, align 4
+  ret i32 %3
+}
Index: test/CodeGen/X86/x86-64-codemodel-medium-internal.ll
===================================================================
--- /dev/null
+++ test/CodeGen/X86/x86-64-codemodel-medium-internal.ll
@@ -0,0 +1,43 @@
+; RUN: llc < %s -code-model=medium | FileCheck -check-prefix CHECK-MEDIUM %s
+; RUN: llc < %s -code-model=medium -relocation-model=pic | FileCheck -check-prefix CHECK-MEDIUM-PIC %s
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+;This is to test the internal global access under PIC/no-PIC medium code model
+;with different sizes
+;This is to ensure the current modification not break the other code path on
+;medium code model handling
+;
+
+@global_arr = internal global <{ i32, i32, [98 x i32] }> <{ i32 2, i32 3, [98 x i32] zeroinitializer }>, align 16
+@global_arr_big = internal global <{ i32, i32, [49998 x i32] }> <{ i32 5, i32 6, [49998 x i32] zeroinitializer }>, align 16
+@t = external dso_local global i32, align 4
+
+define i32 @foo() {
+entry:
+; CHECK-MEDIUM-LABEL:  foo:
+; CHECK-MEDIUM:   movabsq $global_arr+28,
+; CHECK-MEDIUM-PIC-LABEL:  foo:
+; CHECK-MEDIUM-PIC:  addl global_arr+28(%rip),
+  %0 = load i32, i32* getelementptr inbounds ([100 x i32], [100 x i32]* bitcast (<{ i32, i32, [98 x i32] }>* @global_arr to [100 x i32]*), i64 0, i64 7), align 4
+  %1 = load i32, i32* @t, align 4
+  %add = add nsw i32 %1, %0
+  store i32 %add, i32* @t, align 4
+  %2 = load i32, i32* @t, align 4
+  ret i32 %2
+}
+
+define i32 @foo_big() {
+entry:
+; CHECK-MEDIUM-LABEL:  foo_big:
+; CHECK-MEDIUM:   movabsq $global_arr_big+28,
+; CHECK-MEDIUM-PIC-LABEL:  foo_big:
+; CHECK-MEDIUM-PIC:  addl global_arr_big+28(%rip),
+  %0 = load i32, i32* getelementptr inbounds ([50000 x i32], [50000 x i32]* bitcast (<{ i32, i32, [49998 x i32] }>* @global_arr_big to [50000 x i32]*), i64 0, i64 7), align 4
+  %1 = load i32, i32* @t, align 4
+  %add = add nsw i32 %1, %0
+  store i32 %add, i32* @t, align 4
+  %2 = load i32, i32* @t, align 4
+  ret i32 %2
+}
Index: test/CodeGen/X86/x86-64-pic-medium-codemodel.ll
===================================================================
--- /dev/null
+++ test/CodeGen/X86/x86-64-pic-medium-codemodel.ll
@@ -0,0 +1,26 @@
+; RUN: llc < %s -code-model=medium -relocation-model=pic | FileCheck -check-prefix CHECK-MEDIUM %s
+; RUN: llc < %s -code-model=small -relocation-model=pic | FileCheck -check-prefix CHECK-SMALL %s
+
+; This is to test the common global addressing in PIC medium code model
+; The addressing codes should same as the PIC small code model
+; Test one scalar type global variable x
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+@x = common global i32* null, align 8
+
+define i32 @bar() {
+entry:
+; CHECK-MEDIUM-LABEL:  bar:
+; CHECK-MEDIUM:   movq    x@GOTPCREL(%rip), %rax
+; CHECK-SMALL-LABEL:  bar:
+; CHECK-SAMLL:   movq    x@GOTPCREL(%rip), %rax
+  %retval = alloca i32, align 4
+  store i32 0, i32* %retval, align 4
+  %0 = load i32*, i32** @x, align 8
+  call void @foo(i32* %0)
+  ret i32 0
+}
+
+declare void @foo(i32*)