R600/SI: Add pattern for flog2

22 more little piglits with radeonsi.

Reviewed-by: Tom Stellard <thomas.stellard@amd.com>
llvm-svn: 174615
diff --git a/llvm/lib/Target/R600/SIInstructions.td b/llvm/lib/Target/R600/SIInstructions.td
index 50605d0..d33e113 100644
--- a/llvm/lib/Target/R600/SIInstructions.td
+++ b/llvm/lib/Target/R600/SIInstructions.td
@@ -615,7 +615,9 @@
   [(set VReg_32:$dst, (fexp2 AllReg_32:$src0))]
 >;
 defm V_LOG_CLAMP_F32 : VOP1_32 <0x00000026, "V_LOG_CLAMP_F32", []>;
-defm V_LOG_F32 : VOP1_32 <0x00000027, "V_LOG_F32", []>;
+defm V_LOG_F32 : VOP1_32 <0x00000027, "V_LOG_F32",
+  [(set VReg_32:$dst, (flog2 AllReg_32:$src0))]
+>;
 defm V_RCP_CLAMP_F32 : VOP1_32 <0x00000028, "V_RCP_CLAMP_F32", []>;
 defm V_RCP_LEGACY_F32 : VOP1_32 <0x00000029, "V_RCP_LEGACY_F32", []>;
 defm V_RCP_F32 : VOP1_32 <0x0000002a, "V_RCP_F32",