Austin Clements 3839b60014 cmd/{asm,compile,internal/obj}: add "maymorestack" support
This adds a debugging hook for optionally calling a "maymorestack"
function in the prologue of any function that might call morestack
(whether it does at run time or not). The maymorestack function will
let us improve lock checking and add debugging modes that stress
function preemption and stack growth.

Passes toolstash-check -all (except on js/wasm, where toolstash
appears to be broken)

Fixes #48297.

Change-Id: I27197947482b329af75dafb9971fc0d3a52eaf31
Reviewed-on: https://go-review.googlesource.com/c/go/+/359795
Trust: Austin Clements <austin@google.com>
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2021-11-05 00:52:06 +00:00

54 lines
3.2 KiB
Go

// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Debug arguments, set by -d flag.
package base
// Debug holds the parsed debugging configuration values.
var Debug DebugFlags
// DebugFlags defines the debugging configuration values (see var Debug).
// Each struct field is a different value, named for the lower-case of the field name.
// Each field must be an int or string and must have a `help` struct tag.
//
// The -d option takes a comma-separated list of settings.
// Each setting is name=value; for ints, name is short for name=1.
type DebugFlags struct {
Append int `help:"print information about append compilation"`
Checkptr int `help:"instrument unsafe pointer conversions\n0: instrumentation disabled\n1: conversions involving unsafe.Pointer are instrumented\n2: conversions to unsafe.Pointer force heap allocation"`
Closure int `help:"print information about closure compilation"`
DclStack int `help:"run internal dclstack check"`
Defer int `help:"print information about defer compilation"`
DisableNil int `help:"disable nil checks"`
DumpPtrs int `help:"show Node pointers values in dump output"`
DwarfInl int `help:"print information about DWARF inlined function creation"`
Export int `help:"print export data"`
GCProg int `help:"print dump of GC programs"`
InlFuncsWithClosures int `help:"allow functions with closures to be inlined"`
Libfuzzer int `help:"enable coverage instrumentation for libfuzzer"`
LocationLists int `help:"print information about DWARF location list creation"`
Nil int `help:"print information about nil checks"`
NoOpenDefer int `help:"disable open-coded defers"`
PCTab string `help:"print named pc-value table\nOne of: pctospadj, pctofile, pctoline, pctoinline, pctopcdata"`
Panic int `help:"show all compiler panics"`
Slice int `help:"print information about slice compilation"`
SoftFloat int `help:"force compiler to emit soft-float code"`
SyncFrames int `help:"how many writer stack frames to include at sync points in unified export data"`
TypeAssert int `help:"print information about type assertion inlining"`
TypecheckInl int `help:"eager typechecking of inline function bodies"`
Unified int `help:"enable unified IR construction"`
UnifiedQuirks int `help:"enable unified IR construction's quirks mode"`
WB int `help:"print information about write barriers"`
ABIWrap int `help:"print information about ABI wrapper generation"`
MayMoreStack string `help:"call named function before all stack growth checks"`
Any bool // set when any of the debug flags have been set
}
// DebugSSA is called to set a -d ssa/... option.
// If nil, those options are reported as invalid options.
// If DebugSSA returns a non-empty string, that text is reported as a compiler error.
var DebugSSA func(phase, flag string, val int, valString string) string