[AMDGPU] Fix +DumpCode to print an entry label for the first function

Summary:
The +DumpCode attribute is a horrible hack in AMDGPU to embed the
disassembly of the generated code into the elf file. It is used by LLPC
to implement an extension that allows the application to read back the
disassembly of the code.

It tries to print an entry label at the start of every function, but
that didn't work for the first function in the module because
DumpCodeInstEmitter wasn't initialised until EmitFunctionBodyStart
which is too late.

Change-Id: I790d73ddf4f51fd02ab32529380c7cb7c607c4ee

Reviewers: arsenm, tpr, kzhuravl

Reviewed By: arsenm

Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63712

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@364508 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/AMDGPU/AMDGPUAsmPrinter.cpp b/lib/Target/AMDGPU/AMDGPUAsmPrinter.cpp
index cf1ed349302049e4ce13c22bdbef6ceddae804c8..b74a9e631a77545ee5ee24b4718362e3420196b0 100644 (file)
--- a/lib/Target/AMDGPU/AMDGPUAsmPrinter.cpp
+++ b/lib/Target/AMDGPU/AMDGPUAsmPrinter.cpp
@@ -206,18 +206,6 @@ void AMDGPUAsmPrinter::EmitFunctionBodyStart() {
 
   if (STM.isAmdHsaOS())
     HSAMetadataStream->emitKernel(*MF, CurrentProgramInfo);
-
-  DumpCodeInstEmitter = nullptr;
-  if (STM.dumpCode()) {
-    // For -dumpcode, get the assembler out of the streamer, even if it does
-    // not really want to let us have it. This only works with -filetype=obj.
-    bool SaveFlag = OutStreamer->getUseAssemblerInfoForParsing();
-    OutStreamer->setUseAssemblerInfoForParsing(true);
-    MCAssembler *Assembler = OutStreamer->getAssemblerPtr();
-    OutStreamer->setUseAssemblerInfoForParsing(SaveFlag);
-    if (Assembler)
-      DumpCodeInstEmitter = Assembler->getEmitterPtr();
-  }
 }
 
 void AMDGPUAsmPrinter::EmitFunctionBodyEnd() {
@@ -458,6 +446,18 @@ bool AMDGPUAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
     EmitProgramInfoSI(MF, CurrentProgramInfo);
   }
 
+  DumpCodeInstEmitter = nullptr;
+  if (STM.dumpCode()) {
+    // For -dumpcode, get the assembler out of the streamer, even if it does
+    // not really want to let us have it. This only works with -filetype=obj.
+    bool SaveFlag = OutStreamer->getUseAssemblerInfoForParsing();
+    OutStreamer->setUseAssemblerInfoForParsing(true);
+    MCAssembler *Assembler = OutStreamer->getAssemblerPtr();
+    OutStreamer->setUseAssemblerInfoForParsing(SaveFlag);
+    if (Assembler)
+      DumpCodeInstEmitter = Assembler->getEmitterPtr();
+  }
+
   DisasmLines.clear();
   HexLines.clear();
   DisasmLineMaxLen = 0;

diff --git a/test/CodeGen/AMDGPU/debug.ll b/test/CodeGen/AMDGPU/debug.ll
index f149aaddb8eff99b0784ff4db5e88fffd681bcf6..87f1de055405857dffadd5129119bea0e94aa2a1 100644 (file)
--- a/test/CodeGen/AMDGPU/debug.ll
+++ b/test/CodeGen/AMDGPU/debug.ll
@@ -3,6 +3,8 @@
 
 ; Test for a crash in the custom assembly dump code.
 
+; SI: test:
+; SI: BB0_0:
 ; SI: s_endpgm
 define amdgpu_kernel void @test(i32 addrspace(1)* %out) {
   store i32 0, i32 addrspace(1)* %out