[llvm] r219519 - R600/SI: Disable copying of SCC

[Matt Arsenault]

Author: arsenm
Date: Fri Oct 10 12:44:47 2014
New Revision: 219519

URL: http://llvm.org/viewvc/llvm-project?rev=219519&view=rev
Log:
R600/SI: Disable copying of SCC

Modified:
    llvm/trunk/lib/Target/R600/SIRegisterInfo.td

Modified: llvm/trunk/lib/Target/R600/SIRegisterInfo.td
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/R600/SIRegisterInfo.td?rev=219519&r1=219518&r2=219519&view=diff
==============================================================================
--- llvm/trunk/lib/Target/R600/SIRegisterInfo.td (original)
+++ llvm/trunk/lib/Target/R600/SIRegisterInfo.td Fri Oct 10 12:44:47 2014
@@ -170,7 +170,11 @@ def VGPR_512 : RegisterTuples<[sub0, sub
 //===----------------------------------------------------------------------===//
 
 // Special register classes for predicates and the M0 register
-def SCCReg : RegisterClass<"AMDGPU", [i32, i1], 32, (add SCC)>;
+def SCCReg : RegisterClass<"AMDGPU", [i32, i1], 32, (add SCC)> {
+  let CopyCost = -1; // Theoretically it is possible to read from SCC,
+                     // but it should never be necessary.
+}
+
 def VCCReg : RegisterClass<"AMDGPU", [i64, i1], 64, (add VCC)>;
 def EXECReg : RegisterClass<"AMDGPU", [i64, i1], 64, (add EXEC)>;
 def M0Reg : RegisterClass<"AMDGPU", [i32], 32, (add M0)>;