diff options
Diffstat (limited to 'src/cmd/internal/obj/link.go')
| -rw-r--r-- | src/cmd/internal/obj/link.go | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/src/cmd/internal/obj/link.go b/src/cmd/internal/obj/link.go index 977c5c3303..35cb53cbf6 100644 --- a/src/cmd/internal/obj/link.go +++ b/src/cmd/internal/obj/link.go @@ -766,6 +766,17 @@ type Auto struct { Gotype *LSym } +// RegArg provides spill/fill information for a register-resident argument +// to a function. These need spilling/filling in the safepoint/stackgrowth case. +// At the time of fill/spill, the offset must be adjusted by the architecture-dependent +// adjustment to hardware SP that occurs in a call instruction. E.g., for AMD64, +// at Offset+8 because the return address was pushed. +type RegArg struct { + Addr Addr + Reg int16 + Spill, Unspill As +} + // Link holds the context for writing object code from a compiler // to be linker input or for reading that input into the linker. type Link struct { @@ -796,6 +807,7 @@ type Link struct { DebugInfo func(fn *LSym, info *LSym, curfn interface{}) ([]dwarf.Scope, dwarf.InlCalls) // if non-nil, curfn is a *gc.Node GenAbstractFunc func(fn *LSym) Errors int + RegArgs []RegArg InParallel bool // parallel backend phase in effect UseBASEntries bool // use Base Address Selection Entries in location lists and PC ranges @@ -844,6 +856,32 @@ func (ctxt *Link) Logf(format string, args ...interface{}) { ctxt.Bso.Flush() } +func (ctxt *Link) SpillRegisterArgs(last *Prog, pa ProgAlloc) *Prog { + // Spill register args. + for _, ra := range ctxt.RegArgs { + spill := Appendp(last, pa) + spill.As = ra.Spill + spill.From.Type = TYPE_REG + spill.From.Reg = ra.Reg + spill.To = ra.Addr + last = spill + } + return last +} + +func (ctxt *Link) UnspillRegisterArgs(last *Prog, pa ProgAlloc) *Prog { + // Unspill any spilled register args + for _, ra := range ctxt.RegArgs { + unspill := Appendp(last, pa) + unspill.As = ra.Unspill + unspill.From = ra.Addr + unspill.To.Type = TYPE_REG + unspill.To.Reg = ra.Reg + last = unspill + } + return last +} + // The smallest possible offset from the hardware stack pointer to a local // variable on the stack. Architectures that use a link register save its value // on the stack in the function prologue and so always have a pointer between |