AMDGPU: Fix assert on dbg_value instructions

[• tstellarAMD]

LGTM.

[arsenm]

r244728 with some testcase simplification

lib/Target/AMDGPU/AMDGPUAsmPrinter.cpp

void AMDGPUAsmPrinter::getSIProgramInfo(SIProgramInfo &ProgInfo,
   bool VCCUsed = false;
   bool FlatUsed = false;
   const SIRegisterInfo *RI =
       static_cast<const SIRegisterInfo *>(STM.getRegisterInfo());
 
   for (const MachineBasicBlock &MBB : MF) {
     for (const MachineInstr &MI : MBB) {
       // TODO: CodeSize should account for multiple functions.
+
+      // TODO: Should we count size of debug info?
+      if (MI.isDebugValue())
+        continue;
+
+      // FIXME: This is reporting 0 for many instructions.
       CodeSize += MI.getDesc().Size;
 
       unsigned numOperands = MI.getNumOperands();
       for (unsigned op_idx = 0; op_idx < numOperands; op_idx++) {
         const MachineOperand &MO = MI.getOperand(op_idx);
         unsigned width = 0;
         bool isSGPR = false;
 

test/CodeGen/AMDGPU/llvm.dbg.value.ll

+; RUN: llc -O0 -march=amdgcn -mtriple=amdgcn-unknown-amdhsa -verify-machineinstrs < %s | FileCheck %s
+
+; CHECK-LABEL: {{^}}test_debug_value:
+; CHECK: s_load_dwordx2
+; CHECK: DEBUG_VALUE: test_debug_value:globalptr_arg <- SGPR0_SGPR1
+; CHECK: .loc 1 4 0 prologue_end      ; /tmp/simple_debug.cl:4:0
+; CHECK: buffer_store_dword
+; CHECK: .loc 1 5 0                   ; /tmp/simple_debug.cl:5:0
+; CHECK: s_endpgm
+define void @test_debug_value(i32 addrspace(1)* %globalptr_arg) #0 {
+entry:
+  call void @llvm.dbg.value(metadata i32 addrspace(1)* %globalptr_arg, i64 0, metadata !19, metadata !20), !dbg !21
+  store i32 123, i32 addrspace(1)* %globalptr_arg, align 4, !dbg !22
+  ret void, !dbg !23
+}
+
+declare void @llvm.dbg.value(metadata, i64, metadata, metadata) #1
+
+attributes #0 = { nounwind "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-realign-stack" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #1 = { nounwind readnone }
+
+!llvm.dbg.cu = !{!0}
+!opencl.kernels = !{!10}
+!llvm.module.flags = !{!16, !17}
+!llvm.ident = !{!18}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 3.8.0  (llvm/trunk 243556)", isOptimized: false, runtimeVersion: 0, emissionKind: 1, enums: !2, subprograms: !3)
+!1 = !DIFile(filename: "/tmp/<stdin>", directory: "/home/marsenau/src/llvm/build_debug")
+!2 = !{}
+!3 = !{!4}
+!4 = !DISubprogram(name: "test_debug_value", scope: !5, file: !5, line: 2, type: !6, isLocal: false, isDefinition: true, scopeLine: 3, flags: DIFlagPrototyped, isOptimized: false, function: void (i32 addrspace(1)*)* @test_debug_value, variables: !2)
+!5 = !DIFile(filename: "/tmp/simple_debug.cl", directory: "/home/marsenau/src/llvm/build_debug")
+!6 = !DISubroutineType(types: !7)
+!7 = !{null, !8}
+!8 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !9, size: 64, align: 32, extraData: i32 1)
+!9 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
+!10 = !{void (i32 addrspace(1)*)* @test_debug_value, !11, !12, !13, !14, !15}
+!11 = !{!"kernel_arg_addr_space", i32 1}
+!12 = !{!"kernel_arg_access_qual", !"none"}
+!13 = !{!"kernel_arg_type", !"int*"}
+!14 = !{!"kernel_arg_base_type", !"int*"}
+!15 = !{!"kernel_arg_type_qual", !""}
+!16 = !{i32 2, !"Dwarf Version", i32 4}
+!17 = !{i32 2, !"Debug Info Version", i32 3}
+!18 = !{!"clang version 3.8.0  (llvm/trunk 243556)"}
+!19 = !DILocalVariable(tag: DW_TAG_arg_variable, name: "globalptr_arg", arg: 1, scope: !4, file: !5, line: 2, type: !8)
+!20 = !DIExpression()
+!21 = !DILocation(line: 2, scope: !4)
+!22 = !DILocation(line: 4, scope: !4)
+!23 = !DILocation(line: 5, scope: !4)