// Copyright (c) 2026 Petr Balvín <opensource@petrbalvin.org> (https://petrbalvin.org)
// SPDX-License-Identifier: BSD-3-Clause

// The lint side of the extended-instruction layer.  The generated tables and
// the extension registry are two homes for a mnemonic, so a registered
// mnemonic is known wherever the tables are consulted, and a statement pinned
// to the registry is validated by the registry's own encoding, whose refusal
// is the sharper diagnostic the layer carries.

package lint

import (
	"sourcedock.dev/petrbalvin/gasm-sdk/arch"
	"sourcedock.dev/petrbalvin/gasm-sdk/asm"
	"sourcedock.dev/petrbalvin/gasm-sdk/ast"
)

// amd64ExtPinned reports whether a statement belongs to the amd64 extension
// layer alone: the mnemonic is registered in the registry and the encoder
// mirror cannot encode it, the same routing the assembler applies before its
// scalar paths run.  A statement the layer pins never passes through go tool
// asm, so the per-operand portability advice the scalar statements earn is
// noise on it.
func amd64ExtPinned(upper string) bool {
	if _, ok := asm.LookupExtension(arch.AMD64, upper); !ok {
		return false
	}
	return !asm.Encodable(upper)
}

// checkAmd64Extension validates one amd64 statement pinned to the extension
// layer by encoding it through the registry: the layer's own validators carry
// the sharper diagnostic (a mask on a scalar form, rounding on a VL form, k0
// as a write mask), and their refusal is the diagnostic, the same text the
// assembler prints at build time.  A statement the registry encodes is clean:
// the wired layer is the acceptance, not a gap of the generated table.
func checkAmd64Extension(st *ast.Instr, upper string) []Diagnostic {
	_, _, err := asm.EncodeAmd64Statement(upper, st.Operands)
	if err == nil {
		return nil
	}
	return []Diagnostic{{
		Pos:      st.Mnemonic.Pos,
		End:      st.Mnemonic.End,
		Severity: Error,
		Code:     CodeExtensionForm,
		Message:  err.Error(),
	}}
}