Fix missing labels in -mattr=dumpcode output (llvm#1157)

Author: jayfoad

llvm/lib/Target/AMDGPU/MCTargetDesc/AMDGPUELFStreamer.cpp

@@ -9,6 +9,7 @@
 #include "AMDGPUELFStreamer.h"
 #include "llvm/MC/MCAsmBackend.h"
 #include "llvm/MC/MCCodeEmitter.h"
+#include "llvm/MC/MCContext.h"
 #include "llvm/MC/MCELFStreamer.h"
 #include "llvm/MC/MCObjectWriter.h"
 
@@ -23,7 +24,10 @@ class AMDGPUELFStreamer : public MCELFStreamer {
                     std::unique_ptr<MCObjectWriter> OW,
                     std::unique_ptr<MCCodeEmitter> Emitter)
       : MCELFStreamer(Context, std::move(MAB), std::move(OW),
-                      std::move(Emitter)) {}
+                      std::move(Emitter)) {
+    // Give temporary names to basic blocks for the benefit of DumpCode.
+    Context.setUseNamesOnTempLabels(true);
+  }
 };
 
 } // anonymous namespace

llvm/test/CodeGen/AMDGPU/dumpcode.ll

@@ -12,7 +12,7 @@
 ; GFX10-NEXT:   v_cmp_eq_u32_e32 vcc_lo, 0, v2          ; 7D840480
 ; GFX10-NEXT:   s_or_b32 s4, vcc_lo, s4                 ; 8804046A
 ; GFX10-NEXT:   s_andn2_b32 exec_lo, exec_lo, s4        ; 8A7E047E
-; GFX10-NEXT:   s_cbranch_execnz ""                     ; BF890000
+; GFX10-NEXT:   s_cbranch_execnz .LBB0_1                ; BF890000
 ; GFX10-NEXT:   s_or_b32 exec_lo, exec_lo, s4           ; 887E047E
 ; GFX10-NEXT:   s_setpc_b64 s[30:31]                    ; BE80201E