Function annotateAssembly

internal/report/report.go:638–685

annotateAssembly annotates a set of assembly instructions with a set of samples. It returns a set of nodes to display. base is an offset to adjust the sample addresses.

(insts []plugin.Inst, samples graph.Nodes, file plugin.ObjFile)

// set of samples. It returns a set of nodes to display. base is an
// offset to adjust the sample addresses.
func annotateAssembly(insts []plugin.Inst, samples graph.Nodes, file plugin.ObjFile) []assemblyInstruction {
	// Add end marker to simplify printing loop.
	insts = append(insts, plugin.Inst{
		Addr: ^uint64(0),
	})

	// Ensure samples are sorted by address.
	samples.Sort(graph.AddressOrder)

	s := 0
	asm := make([]assemblyInstruction, 0, len(insts))
	for ix, in := range insts[:len(insts)-1] {
		n := assemblyInstruction{
			address:     in.Addr,
			instruction: in.Text,
			function:    in.Function,
			line:        in.Line,
		}
		if in.File != "" {
			n.file = filepath.Base(in.File)
		}

		// Sum all the samples until the next instruction (to account
		// for samples attributed to the middle of an instruction).
		for next := insts[ix+1].Addr; s < len(samples); s++ {
			if addr, err := file.ObjAddr(samples[s].Info.Address); err != nil || addr >= next {
				break
			}
			sample := samples[s]
			n.flatDiv += sample.FlatDiv
			n.flat += sample.Flat
			n.cumDiv += sample.CumDiv
			n.cum += sample.Cum
			if f := sample.Info.File; f != "" && n.file == "" {
				n.file = filepath.Base(f)
			}
			if ln := sample.Info.Lineno; ln != 0 && n.line == 0 {
				n.line = ln
			}
			if f := sample.Info.Name; f != "" && n.function == "" {
				n.function = f
			}
		}
		asm = append(asm, n)
	}

	return asm
}

// valueOrDot formats a value according to a report, intercepting zero
// values.