diff options
Diffstat (limited to 'src/cmd/asm/internal/asm/parse.go')
| -rw-r--r-- | src/cmd/asm/internal/asm/parse.go | 36 |
1 files changed, 34 insertions, 2 deletions
diff --git a/src/cmd/asm/internal/asm/parse.go b/src/cmd/asm/internal/asm/parse.go index 05db95b420..14539dc911 100644 --- a/src/cmd/asm/internal/asm/parse.go +++ b/src/cmd/asm/internal/asm/parse.go @@ -273,7 +273,7 @@ func (p *Parser) operand(a *obj.Addr) bool { // Register: R1 if tok.ScanToken == scanner.Ident && p.atStartOfRegister(name) { - if lex.IsRegisterShift(p.peek()) { + if p.atRegisterShift() { // ARM shifted register such as R1<<R2 or R1>>2. a.Type = obj.TYPE_SHIFT a.Offset = p.registerShift(tok.String(), prefix) @@ -381,6 +381,25 @@ func (p *Parser) atStartOfRegister(name string) bool { return p.arch.RegisterPrefix[name] && p.peek() == '(' } +// atRegisterShift reports whether we are at the start of an ARM shifted register. +// We have consumed the register or R prefix. +func (p *Parser) atRegisterShift() bool { + // ARM only. + if p.arch.Thechar != '5' { + return false + } + // R1<<... + if lex.IsRegisterShift(p.peek()) { + return true + } + // R(1)<<... Ugly check. TODO: Rethink how we handle ARM register shifts to be + // less special. + if p.peek() != '(' || len(p.input)-p.inputPos < 4 { + return false + } + return p.at('(', scanner.Int, ')') && lex.IsRegisterShift(p.input[p.inputPos+3].ScanToken) +} + // registerReference parses a register given either the name, R10, or a parenthesized form, SPR(10). func (p *Parser) registerReference(name string) (int16, bool) { r, present := p.arch.Register[name] @@ -655,7 +674,7 @@ func (p *Parser) registerIndirect(a *obj.Addr, prefix rune) { // registerList parses an ARM register list expression, a list of registers in []. // There may be comma-separated ranges or individual registers, as in -// [R1,R3-R5,R7]. Only R0 through R15 may appear. +// [R1,R3-R5]. Only R0 through R15 may appear. // The opening bracket has been consumed. func (p *Parser) registerList(a *obj.Addr) { // One range per loop. @@ -917,3 +936,16 @@ func (p *Parser) have(token lex.ScanToken) bool { } return false } + +// at reports whether the next tokens are as requested. +func (p *Parser) at(next ...lex.ScanToken) bool { + if len(p.input)-p.inputPos < len(next) { + return false + } + for i, r := range next { + if p.input[p.inputPos+i].ScanToken != r { + return false + } + } + return true +} |