"fmt"
"go/constant"
"go/token"
"os"
"strings"
"cmd/compile/internal/base"
"cmd/compile/internal/ir"
"cmd/compile/internal/reflectdata"
"cmd/compile/internal/staticdata"
"cmd/compile/internal/typecheck"
"cmd/compile/internal/types"
"cmd/internal/obj"
"cmd/internal/objabi"
"cmd/internal/src"
MapInitToVar is the inverse of VarToMapInit; it maintains a mapping from a compiler-generated init function to the map the function is initializing.
var MapInitToVar map[*ir.Func]*ir.Namemapinitgen is a counter used to uniquify compiler-generated map init functions.
var mapinitgen intvar statuniqgen intvarToMapInit holds book-keeping state for global map initialization; it records the init function created by the compiler to host the initialization code for the map in question.
var varToMapInit map[*ir.Name]*ir.Funcconst wrapGlobalMapInitSizeThreshold = 20type Entry struct {
Xoffset int64
Expr ir.Node
}type Plan struct {
E []Entry
}An Schedule is used to decompose assignment statements into static and dynamic initialization parts. Static initializations are handled by populating variables' linker symbol data, while dynamic initializations are accumulated to be executed in order.
type Schedule struct {
Out []ir.Node
Plans map[ir.Node]*Plan
Temps map[ir.Node]*ir.Name
seenMutation bool
}AddKeepRelocations adds a dummy "R_KEEP" relocation from each global map variable V to its associated outlined init function. These relocation ensure that if the map var itself is determined to be reachable at link time, we also mark the init function as reachable.
func AddKeepRelocations()AnySideEffects reports whether n contains any operations that could have observable side effects.
func AnySideEffects(n ir.Node) boolOutlineMapInits replaces global map initializers with outlined calls to separate "map init" functions (where possible and profitable), to facilitate better dead-code elimination by the linker.
func OutlineMapInits(fn *ir.Func)func (s *Schedule) StaticAssign(l *ir.Name, loff int64, r ir.Node, typ *types.Type) boolStaticInit adds an initialization statement n to the schedule.
func (s *Schedule) StaticInit(n ir.Node)StaticLoc returns the static address of n, if n has one, or else nil.
func StaticLoc(n ir.Node) (name *ir.Name, offset int64, ok bool)StaticName returns a name backed by a (writable) static data symbol.
func StaticName(t *types.Type) *ir.Namefunc addStr(n *ir.AddStringExpr) ir.Nodefunc (s *Schedule) addvalue(p *Plan, xoffset int64, n ir.Node)allBlank reports whether every node in exprs is blank.
func allBlank(exprs []ir.Node) boolfunc (s *Schedule) append(n ir.Node)canRepeat reports whether executing n multiple times has the same effect as assigning n to a single variable and using that variable multiple times.
func canRepeat(n ir.Node) boolfunc getlit(lit ir.Node) intfunc (s *Schedule) initplan(n ir.Node)func isSideEffect(n ir.Node) boolfunc isvaluelit(n ir.Node) boolmayModifyPkgVar reports whether expression n may modify any package-scope variables declared within the current package.
func mayModifyPkgVar(n ir.Node) boolrecordFuncForVar establishes a mapping between global map var "v" and outlined init function "fn" (and vice versa); so that we can use the mappings later on to update relocations.
func recordFuncForVar(v *ir.Name, fn *ir.Func)func (s *Schedule) staticAssignInlinedCall(l *ir.Name, loff int64, call *ir.InlinedCallExpr, typ *types.Type) boollike staticassign but we are copying an already initialized value r.
func (s *Schedule) staticcopy(l *ir.Name, loff int64, rn *ir.Name, typ *types.Type) boolfunc subst(n ir.Node, m map[*ir.Name]ir.Node) (ir.Node, bool)truncate returns the result of force converting c to type t, truncating its value as needed, like a conversion of a variable. If the conversion is too difficult, truncate returns nil, false.
func truncate(c ir.Node, t *types.Type) (ir.Node, bool)tryStaticInit attempts to statically execute an initialization statement and reports whether it succeeded.
func (s *Schedule) tryStaticInit(n ir.Node) booltryWrapGlobalInit returns a new outlined function to contain global initializer statement n, if possible and worthwhile. Otherwise, it returns nil. Currently, it outlines map assignment statements with large, side-effect-free RHS expressions.
func tryWrapGlobalInit(n ir.Node) *ir.FuncGenerated with Arrow