Index: llvm/trunk/lib/Target/AMDGPU/SOPInstructions.td
===================================================================
--- llvm/trunk/lib/Target/AMDGPU/SOPInstructions.td
+++ llvm/trunk/lib/Target/AMDGPU/SOPInstructions.td
@@ -434,7 +434,7 @@
 
 def S_CBRANCH_G_FORK : SOP2_Pseudo <
   "s_cbranch_g_fork", (outs),
-  (ins SReg_64:$src0, SReg_64:$src1),
+  (ins SCSrc_b64:$src0, SCSrc_b64:$src1),
   "$src0, $src1"
 > {
   let has_sdst = 0;
Index: llvm/trunk/test/MC/AMDGPU/sop2-err.s
===================================================================
--- llvm/trunk/test/MC/AMDGPU/sop2-err.s
+++ llvm/trunk/test/MC/AMDGPU/sop2-err.s
@@ -0,0 +1,7 @@
+// RUN: not llvm-mc -arch=amdgcn %s 2>&1 | FileCheck -check-prefix=GCN %s
+
+s_cbranch_g_fork 100, s[6:7]
+// GCN: error: invalid operand for instruction
+
+s_cbranch_g_fork s[6:7], 100
+// GCN: error: invalid operand for instruction
Index: llvm/trunk/test/MC/AMDGPU/sop2.s
===================================================================
--- llvm/trunk/test/MC/AMDGPU/sop2.s
+++ llvm/trunk/test/MC/AMDGPU/sop2.s
@@ -160,6 +160,14 @@
 // SICI: s_cbranch_g_fork s[4:5], s[6:7] ; encoding: [0x04,0x06,0x80,0x95]
 // VI:   s_cbranch_g_fork s[4:5], s[6:7] ; encoding: [0x04,0x06,0x80,0x94]
 
+s_cbranch_g_fork 1, s[6:7]
+// SICI: s_cbranch_g_fork 1, s[6:7] ; encoding: [0x81,0x06,0x80,0x95]
+// VI:   s_cbranch_g_fork 1, s[6:7] ; encoding: [0x81,0x06,0x80,0x94]
+
+s_cbranch_g_fork s[6:7], 2
+// SICI: s_cbranch_g_fork s[6:7], 2 ; encoding: [0x06,0x82,0x80,0x95]
+// VI:   s_cbranch_g_fork s[6:7], 2 ; encoding: [0x06,0x82,0x80,0x94]
+
 s_absdiff_i32 s2, s4, s6
 // SICI: s_absdiff_i32 s2, s4, s6 ; encoding: [0x04,0x06,0x02,0x96]
 // VI:   s_absdiff_i32 s2, s4, s6 ; encoding: [0x04,0x06,0x02,0x95]