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Diffstat (limited to 'vendor/github.com/twitchyliquid64/golang-asm/obj/arm/obj5.go')
-rw-r--r--vendor/github.com/twitchyliquid64/golang-asm/obj/arm/obj5.go784
1 files changed, 0 insertions, 784 deletions
diff --git a/vendor/github.com/twitchyliquid64/golang-asm/obj/arm/obj5.go b/vendor/github.com/twitchyliquid64/golang-asm/obj/arm/obj5.go
deleted file mode 100644
index 50e0698a3..000000000
--- a/vendor/github.com/twitchyliquid64/golang-asm/obj/arm/obj5.go
+++ /dev/null
@@ -1,784 +0,0 @@
-// Derived from Inferno utils/5c/swt.c
-// https://bitbucket.org/inferno-os/inferno-os/src/master/utils/5c/swt.c
-//
-// Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved.
-// Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
-// Portions Copyright © 1997-1999 Vita Nuova Limited
-// Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
-// Portions Copyright © 2004,2006 Bruce Ellis
-// Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
-// Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
-// Portions Copyright © 2009 The Go Authors. All rights reserved.
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in
-// all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-// THE SOFTWARE.
-
-package arm
-
-import (
- "github.com/twitchyliquid64/golang-asm/obj"
- "github.com/twitchyliquid64/golang-asm/objabi"
- "github.com/twitchyliquid64/golang-asm/sys"
-)
-
-var progedit_tlsfallback *obj.LSym
-
-func progedit(ctxt *obj.Link, p *obj.Prog, newprog obj.ProgAlloc) {
- p.From.Class = 0
- p.To.Class = 0
-
- c := ctxt5{ctxt: ctxt, newprog: newprog}
-
- // Rewrite B/BL to symbol as TYPE_BRANCH.
- switch p.As {
- case AB, ABL, obj.ADUFFZERO, obj.ADUFFCOPY:
- if p.To.Type == obj.TYPE_MEM && (p.To.Name == obj.NAME_EXTERN || p.To.Name == obj.NAME_STATIC) && p.To.Sym != nil {
- p.To.Type = obj.TYPE_BRANCH
- }
- }
-
- // Replace TLS register fetches on older ARM processors.
- switch p.As {
- // Treat MRC 15, 0, <reg>, C13, C0, 3 specially.
- case AMRC:
- if p.To.Offset&0xffff0fff == 0xee1d0f70 {
- // Because the instruction might be rewritten to a BL which returns in R0
- // the register must be zero.
- if p.To.Offset&0xf000 != 0 {
- ctxt.Diag("%v: TLS MRC instruction must write to R0 as it might get translated into a BL instruction", p.Line())
- }
-
- if objabi.GOARM < 7 {
- // Replace it with BL runtime.read_tls_fallback(SB) for ARM CPUs that lack the tls extension.
- if progedit_tlsfallback == nil {
- progedit_tlsfallback = ctxt.Lookup("runtime.read_tls_fallback")
- }
-
- // MOVW LR, R11
- p.As = AMOVW
-
- p.From.Type = obj.TYPE_REG
- p.From.Reg = REGLINK
- p.To.Type = obj.TYPE_REG
- p.To.Reg = REGTMP
-
- // BL runtime.read_tls_fallback(SB)
- p = obj.Appendp(p, newprog)
-
- p.As = ABL
- p.To.Type = obj.TYPE_BRANCH
- p.To.Sym = progedit_tlsfallback
- p.To.Offset = 0
-
- // MOVW R11, LR
- p = obj.Appendp(p, newprog)
-
- p.As = AMOVW
- p.From.Type = obj.TYPE_REG
- p.From.Reg = REGTMP
- p.To.Type = obj.TYPE_REG
- p.To.Reg = REGLINK
- break
- }
- }
-
- // Otherwise, MRC/MCR instructions need no further treatment.
- p.As = AWORD
- }
-
- // Rewrite float constants to values stored in memory.
- switch p.As {
- case AMOVF:
- if p.From.Type == obj.TYPE_FCONST && c.chipfloat5(p.From.Val.(float64)) < 0 && (c.chipzero5(p.From.Val.(float64)) < 0 || p.Scond&C_SCOND != C_SCOND_NONE) {
- f32 := float32(p.From.Val.(float64))
- p.From.Type = obj.TYPE_MEM
- p.From.Sym = ctxt.Float32Sym(f32)
- p.From.Name = obj.NAME_EXTERN
- p.From.Offset = 0
- }
-
- case AMOVD:
- if p.From.Type == obj.TYPE_FCONST && c.chipfloat5(p.From.Val.(float64)) < 0 && (c.chipzero5(p.From.Val.(float64)) < 0 || p.Scond&C_SCOND != C_SCOND_NONE) {
- p.From.Type = obj.TYPE_MEM
- p.From.Sym = ctxt.Float64Sym(p.From.Val.(float64))
- p.From.Name = obj.NAME_EXTERN
- p.From.Offset = 0
- }
- }
-
- if ctxt.Flag_dynlink {
- c.rewriteToUseGot(p)
- }
-}
-
-// Rewrite p, if necessary, to access global data via the global offset table.
-func (c *ctxt5) rewriteToUseGot(p *obj.Prog) {
- if p.As == obj.ADUFFCOPY || p.As == obj.ADUFFZERO {
- // ADUFFxxx $offset
- // becomes
- // MOVW runtime.duffxxx@GOT, R9
- // ADD $offset, R9
- // CALL (R9)
- var sym *obj.LSym
- if p.As == obj.ADUFFZERO {
- sym = c.ctxt.Lookup("runtime.duffzero")
- } else {
- sym = c.ctxt.Lookup("runtime.duffcopy")
- }
- offset := p.To.Offset
- p.As = AMOVW
- p.From.Type = obj.TYPE_MEM
- p.From.Name = obj.NAME_GOTREF
- p.From.Sym = sym
- p.To.Type = obj.TYPE_REG
- p.To.Reg = REG_R9
- p.To.Name = obj.NAME_NONE
- p.To.Offset = 0
- p.To.Sym = nil
- p1 := obj.Appendp(p, c.newprog)
- p1.As = AADD
- p1.From.Type = obj.TYPE_CONST
- p1.From.Offset = offset
- p1.To.Type = obj.TYPE_REG
- p1.To.Reg = REG_R9
- p2 := obj.Appendp(p1, c.newprog)
- p2.As = obj.ACALL
- p2.To.Type = obj.TYPE_MEM
- p2.To.Reg = REG_R9
- return
- }
-
- // We only care about global data: NAME_EXTERN means a global
- // symbol in the Go sense, and p.Sym.Local is true for a few
- // internally defined symbols.
- if p.From.Type == obj.TYPE_ADDR && p.From.Name == obj.NAME_EXTERN && !p.From.Sym.Local() {
- // MOVW $sym, Rx becomes MOVW sym@GOT, Rx
- // MOVW $sym+<off>, Rx becomes MOVW sym@GOT, Rx; ADD <off>, Rx
- if p.As != AMOVW {
- c.ctxt.Diag("do not know how to handle TYPE_ADDR in %v with -dynlink", p)
- }
- if p.To.Type != obj.TYPE_REG {
- c.ctxt.Diag("do not know how to handle LEAQ-type insn to non-register in %v with -dynlink", p)
- }
- p.From.Type = obj.TYPE_MEM
- p.From.Name = obj.NAME_GOTREF
- if p.From.Offset != 0 {
- q := obj.Appendp(p, c.newprog)
- q.As = AADD
- q.From.Type = obj.TYPE_CONST
- q.From.Offset = p.From.Offset
- q.To = p.To
- p.From.Offset = 0
- }
- }
- if p.GetFrom3() != nil && p.GetFrom3().Name == obj.NAME_EXTERN {
- c.ctxt.Diag("don't know how to handle %v with -dynlink", p)
- }
- var source *obj.Addr
- // MOVx sym, Ry becomes MOVW sym@GOT, R9; MOVx (R9), Ry
- // MOVx Ry, sym becomes MOVW sym@GOT, R9; MOVx Ry, (R9)
- // An addition may be inserted between the two MOVs if there is an offset.
- if p.From.Name == obj.NAME_EXTERN && !p.From.Sym.Local() {
- if p.To.Name == obj.NAME_EXTERN && !p.To.Sym.Local() {
- c.ctxt.Diag("cannot handle NAME_EXTERN on both sides in %v with -dynlink", p)
- }
- source = &p.From
- } else if p.To.Name == obj.NAME_EXTERN && !p.To.Sym.Local() {
- source = &p.To
- } else {
- return
- }
- if p.As == obj.ATEXT || p.As == obj.AFUNCDATA || p.As == obj.ACALL || p.As == obj.ARET || p.As == obj.AJMP {
- return
- }
- if source.Sym.Type == objabi.STLSBSS {
- return
- }
- if source.Type != obj.TYPE_MEM {
- c.ctxt.Diag("don't know how to handle %v with -dynlink", p)
- }
- p1 := obj.Appendp(p, c.newprog)
- p2 := obj.Appendp(p1, c.newprog)
-
- p1.As = AMOVW
- p1.From.Type = obj.TYPE_MEM
- p1.From.Sym = source.Sym
- p1.From.Name = obj.NAME_GOTREF
- p1.To.Type = obj.TYPE_REG
- p1.To.Reg = REG_R9
-
- p2.As = p.As
- p2.From = p.From
- p2.To = p.To
- if p.From.Name == obj.NAME_EXTERN {
- p2.From.Reg = REG_R9
- p2.From.Name = obj.NAME_NONE
- p2.From.Sym = nil
- } else if p.To.Name == obj.NAME_EXTERN {
- p2.To.Reg = REG_R9
- p2.To.Name = obj.NAME_NONE
- p2.To.Sym = nil
- } else {
- return
- }
- obj.Nopout(p)
-}
-
-// Prog.mark
-const (
- FOLL = 1 << 0
- LABEL = 1 << 1
- LEAF = 1 << 2
-)
-
-func preprocess(ctxt *obj.Link, cursym *obj.LSym, newprog obj.ProgAlloc) {
- autosize := int32(0)
-
- if cursym.Func.Text == nil || cursym.Func.Text.Link == nil {
- return
- }
-
- c := ctxt5{ctxt: ctxt, cursym: cursym, newprog: newprog}
-
- p := c.cursym.Func.Text
- autoffset := int32(p.To.Offset)
- if autoffset == -4 {
- // Historical way to mark NOFRAME.
- p.From.Sym.Set(obj.AttrNoFrame, true)
- autoffset = 0
- }
- if autoffset < 0 || autoffset%4 != 0 {
- c.ctxt.Diag("frame size %d not 0 or a positive multiple of 4", autoffset)
- }
- if p.From.Sym.NoFrame() {
- if autoffset != 0 {
- c.ctxt.Diag("NOFRAME functions must have a frame size of 0, not %d", autoffset)
- }
- }
-
- cursym.Func.Locals = autoffset
- cursym.Func.Args = p.To.Val.(int32)
-
- /*
- * find leaf subroutines
- */
- for p := cursym.Func.Text; p != nil; p = p.Link {
- switch p.As {
- case obj.ATEXT:
- p.Mark |= LEAF
-
- case ADIV, ADIVU, AMOD, AMODU:
- cursym.Func.Text.Mark &^= LEAF
-
- case ABL,
- ABX,
- obj.ADUFFZERO,
- obj.ADUFFCOPY:
- cursym.Func.Text.Mark &^= LEAF
- }
- }
-
- var q2 *obj.Prog
- for p := cursym.Func.Text; p != nil; p = p.Link {
- o := p.As
- switch o {
- case obj.ATEXT:
- autosize = autoffset
-
- if p.Mark&LEAF != 0 && autosize == 0 {
- // A leaf function with no locals has no frame.
- p.From.Sym.Set(obj.AttrNoFrame, true)
- }
-
- if !p.From.Sym.NoFrame() {
- // If there is a stack frame at all, it includes
- // space to save the LR.
- autosize += 4
- }
-
- if autosize == 0 && cursym.Func.Text.Mark&LEAF == 0 {
- // A very few functions that do not return to their caller
- // are not identified as leaves but still have no frame.
- if ctxt.Debugvlog {
- ctxt.Logf("save suppressed in: %s\n", cursym.Name)
- }
-
- cursym.Func.Text.Mark |= LEAF
- }
-
- // FP offsets need an updated p.To.Offset.
- p.To.Offset = int64(autosize) - 4
-
- if cursym.Func.Text.Mark&LEAF != 0 {
- cursym.Set(obj.AttrLeaf, true)
- if p.From.Sym.NoFrame() {
- break
- }
- }
-
- if !p.From.Sym.NoSplit() {
- p = c.stacksplit(p, autosize) // emit split check
- }
-
- // MOVW.W R14,$-autosize(SP)
- p = obj.Appendp(p, c.newprog)
-
- p.As = AMOVW
- p.Scond |= C_WBIT
- p.From.Type = obj.TYPE_REG
- p.From.Reg = REGLINK
- p.To.Type = obj.TYPE_MEM
- p.To.Offset = int64(-autosize)
- p.To.Reg = REGSP
- p.Spadj = autosize
-
- if cursym.Func.Text.From.Sym.Wrapper() {
- // if(g->panic != nil && g->panic->argp == FP) g->panic->argp = bottom-of-frame
- //
- // MOVW g_panic(g), R1
- // CMP $0, R1
- // B.NE checkargp
- // end:
- // NOP
- // ... function ...
- // checkargp:
- // MOVW panic_argp(R1), R2
- // ADD $(autosize+4), R13, R3
- // CMP R2, R3
- // B.NE end
- // ADD $4, R13, R4
- // MOVW R4, panic_argp(R1)
- // B end
- //
- // The NOP is needed to give the jumps somewhere to land.
- // It is a liblink NOP, not an ARM NOP: it encodes to 0 instruction bytes.
-
- p = obj.Appendp(p, newprog)
- p.As = AMOVW
- p.From.Type = obj.TYPE_MEM
- p.From.Reg = REGG
- p.From.Offset = 4 * int64(ctxt.Arch.PtrSize) // G.panic
- p.To.Type = obj.TYPE_REG
- p.To.Reg = REG_R1
-
- p = obj.Appendp(p, newprog)
- p.As = ACMP
- p.From.Type = obj.TYPE_CONST
- p.From.Offset = 0
- p.Reg = REG_R1
-
- // B.NE checkargp
- bne := obj.Appendp(p, newprog)
- bne.As = ABNE
- bne.To.Type = obj.TYPE_BRANCH
-
- // end: NOP
- end := obj.Appendp(bne, newprog)
- end.As = obj.ANOP
-
- // find end of function
- var last *obj.Prog
- for last = end; last.Link != nil; last = last.Link {
- }
-
- // MOVW panic_argp(R1), R2
- mov := obj.Appendp(last, newprog)
- mov.As = AMOVW
- mov.From.Type = obj.TYPE_MEM
- mov.From.Reg = REG_R1
- mov.From.Offset = 0 // Panic.argp
- mov.To.Type = obj.TYPE_REG
- mov.To.Reg = REG_R2
-
- // B.NE branch target is MOVW above
- bne.To.SetTarget(mov)
-
- // ADD $(autosize+4), R13, R3
- p = obj.Appendp(mov, newprog)
- p.As = AADD
- p.From.Type = obj.TYPE_CONST
- p.From.Offset = int64(autosize) + 4
- p.Reg = REG_R13
- p.To.Type = obj.TYPE_REG
- p.To.Reg = REG_R3
-
- // CMP R2, R3
- p = obj.Appendp(p, newprog)
- p.As = ACMP
- p.From.Type = obj.TYPE_REG
- p.From.Reg = REG_R2
- p.Reg = REG_R3
-
- // B.NE end
- p = obj.Appendp(p, newprog)
- p.As = ABNE
- p.To.Type = obj.TYPE_BRANCH
- p.To.SetTarget(end)
-
- // ADD $4, R13, R4
- p = obj.Appendp(p, newprog)
- p.As = AADD
- p.From.Type = obj.TYPE_CONST
- p.From.Offset = 4
- p.Reg = REG_R13
- p.To.Type = obj.TYPE_REG
- p.To.Reg = REG_R4
-
- // MOVW R4, panic_argp(R1)
- p = obj.Appendp(p, newprog)
- p.As = AMOVW
- p.From.Type = obj.TYPE_REG
- p.From.Reg = REG_R4
- p.To.Type = obj.TYPE_MEM
- p.To.Reg = REG_R1
- p.To.Offset = 0 // Panic.argp
-
- // B end
- p = obj.Appendp(p, newprog)
- p.As = AB
- p.To.Type = obj.TYPE_BRANCH
- p.To.SetTarget(end)
-
- // reset for subsequent passes
- p = end
- }
-
- case obj.ARET:
- nocache(p)
- if cursym.Func.Text.Mark&LEAF != 0 {
- if autosize == 0 {
- p.As = AB
- p.From = obj.Addr{}
- if p.To.Sym != nil { // retjmp
- p.To.Type = obj.TYPE_BRANCH
- } else {
- p.To.Type = obj.TYPE_MEM
- p.To.Offset = 0
- p.To.Reg = REGLINK
- }
-
- break
- }
- }
-
- p.As = AMOVW
- p.Scond |= C_PBIT
- p.From.Type = obj.TYPE_MEM
- p.From.Offset = int64(autosize)
- p.From.Reg = REGSP
- p.To.Type = obj.TYPE_REG
- p.To.Reg = REGPC
-
- // If there are instructions following
- // this ARET, they come from a branch
- // with the same stackframe, so no spadj.
- if p.To.Sym != nil { // retjmp
- p.To.Reg = REGLINK
- q2 = obj.Appendp(p, newprog)
- q2.As = AB
- q2.To.Type = obj.TYPE_BRANCH
- q2.To.Sym = p.To.Sym
- p.To.Sym = nil
- p = q2
- }
-
- case AADD:
- if p.From.Type == obj.TYPE_CONST && p.From.Reg == 0 && p.To.Type == obj.TYPE_REG && p.To.Reg == REGSP {
- p.Spadj = int32(-p.From.Offset)
- }
-
- case ASUB:
- if p.From.Type == obj.TYPE_CONST && p.From.Reg == 0 && p.To.Type == obj.TYPE_REG && p.To.Reg == REGSP {
- p.Spadj = int32(p.From.Offset)
- }
-
- case ADIV, ADIVU, AMOD, AMODU:
- if cursym.Func.Text.From.Sym.NoSplit() {
- ctxt.Diag("cannot divide in NOSPLIT function")
- }
- const debugdivmod = false
- if debugdivmod {
- break
- }
- if p.From.Type != obj.TYPE_REG {
- break
- }
- if p.To.Type != obj.TYPE_REG {
- break
- }
-
- // Make copy because we overwrite p below.
- q1 := *p
- if q1.Reg == REGTMP || q1.Reg == 0 && q1.To.Reg == REGTMP {
- ctxt.Diag("div already using REGTMP: %v", p)
- }
-
- /* MOV m(g),REGTMP */
- p.As = AMOVW
- p.Pos = q1.Pos
- p.From.Type = obj.TYPE_MEM
- p.From.Reg = REGG
- p.From.Offset = 6 * 4 // offset of g.m
- p.Reg = 0
- p.To.Type = obj.TYPE_REG
- p.To.Reg = REGTMP
-
- /* MOV a,m_divmod(REGTMP) */
- p = obj.Appendp(p, newprog)
- p.As = AMOVW
- p.Pos = q1.Pos
- p.From.Type = obj.TYPE_REG
- p.From.Reg = q1.From.Reg
- p.To.Type = obj.TYPE_MEM
- p.To.Reg = REGTMP
- p.To.Offset = 8 * 4 // offset of m.divmod
-
- /* MOV b, R8 */
- p = obj.Appendp(p, newprog)
- p.As = AMOVW
- p.Pos = q1.Pos
- p.From.Type = obj.TYPE_REG
- p.From.Reg = q1.Reg
- if q1.Reg == 0 {
- p.From.Reg = q1.To.Reg
- }
- p.To.Type = obj.TYPE_REG
- p.To.Reg = REG_R8
- p.To.Offset = 0
-
- /* CALL appropriate */
- p = obj.Appendp(p, newprog)
- p.As = ABL
- p.Pos = q1.Pos
- p.To.Type = obj.TYPE_BRANCH
- switch o {
- case ADIV:
- p.To.Sym = symdiv
- case ADIVU:
- p.To.Sym = symdivu
- case AMOD:
- p.To.Sym = symmod
- case AMODU:
- p.To.Sym = symmodu
- }
-
- /* MOV REGTMP, b */
- p = obj.Appendp(p, newprog)
- p.As = AMOVW
- p.Pos = q1.Pos
- p.From.Type = obj.TYPE_REG
- p.From.Reg = REGTMP
- p.From.Offset = 0
- p.To.Type = obj.TYPE_REG
- p.To.Reg = q1.To.Reg
-
- case AMOVW:
- if (p.Scond&C_WBIT != 0) && p.To.Type == obj.TYPE_MEM && p.To.Reg == REGSP {
- p.Spadj = int32(-p.To.Offset)
- }
- if (p.Scond&C_PBIT != 0) && p.From.Type == obj.TYPE_MEM && p.From.Reg == REGSP && p.To.Reg != REGPC {
- p.Spadj = int32(-p.From.Offset)
- }
- if p.From.Type == obj.TYPE_ADDR && p.From.Reg == REGSP && p.To.Type == obj.TYPE_REG && p.To.Reg == REGSP {
- p.Spadj = int32(-p.From.Offset)
- }
-
- case obj.AGETCALLERPC:
- if cursym.Leaf() {
- /* MOVW LR, Rd */
- p.As = AMOVW
- p.From.Type = obj.TYPE_REG
- p.From.Reg = REGLINK
- } else {
- /* MOVW (RSP), Rd */
- p.As = AMOVW
- p.From.Type = obj.TYPE_MEM
- p.From.Reg = REGSP
- }
- }
- }
-}
-
-func (c *ctxt5) stacksplit(p *obj.Prog, framesize int32) *obj.Prog {
- // MOVW g_stackguard(g), R1
- p = obj.Appendp(p, c.newprog)
-
- p.As = AMOVW
- p.From.Type = obj.TYPE_MEM
- p.From.Reg = REGG
- p.From.Offset = 2 * int64(c.ctxt.Arch.PtrSize) // G.stackguard0
- if c.cursym.CFunc() {
- p.From.Offset = 3 * int64(c.ctxt.Arch.PtrSize) // G.stackguard1
- }
- p.To.Type = obj.TYPE_REG
- p.To.Reg = REG_R1
-
- // Mark the stack bound check and morestack call async nonpreemptible.
- // If we get preempted here, when resumed the preemption request is
- // cleared, but we'll still call morestack, which will double the stack
- // unnecessarily. See issue #35470.
- p = c.ctxt.StartUnsafePoint(p, c.newprog)
-
- if framesize <= objabi.StackSmall {
- // small stack: SP < stackguard
- // CMP stackguard, SP
- p = obj.Appendp(p, c.newprog)
-
- p.As = ACMP
- p.From.Type = obj.TYPE_REG
- p.From.Reg = REG_R1
- p.Reg = REGSP
- } else if framesize <= objabi.StackBig {
- // large stack: SP-framesize < stackguard-StackSmall
- // MOVW $-(framesize-StackSmall)(SP), R2
- // CMP stackguard, R2
- p = obj.Appendp(p, c.newprog)
-
- p.As = AMOVW
- p.From.Type = obj.TYPE_ADDR
- p.From.Reg = REGSP
- p.From.Offset = -(int64(framesize) - objabi.StackSmall)
- p.To.Type = obj.TYPE_REG
- p.To.Reg = REG_R2
-
- p = obj.Appendp(p, c.newprog)
- p.As = ACMP
- p.From.Type = obj.TYPE_REG
- p.From.Reg = REG_R1
- p.Reg = REG_R2
- } else {
- // Such a large stack we need to protect against wraparound
- // if SP is close to zero.
- // SP-stackguard+StackGuard < framesize + (StackGuard-StackSmall)
- // The +StackGuard on both sides is required to keep the left side positive:
- // SP is allowed to be slightly below stackguard. See stack.h.
- // CMP $StackPreempt, R1
- // MOVW.NE $StackGuard(SP), R2
- // SUB.NE R1, R2
- // MOVW.NE $(framesize+(StackGuard-StackSmall)), R3
- // CMP.NE R3, R2
- p = obj.Appendp(p, c.newprog)
-
- p.As = ACMP
- p.From.Type = obj.TYPE_CONST
- p.From.Offset = int64(uint32(objabi.StackPreempt & (1<<32 - 1)))
- p.Reg = REG_R1
-
- p = obj.Appendp(p, c.newprog)
- p.As = AMOVW
- p.From.Type = obj.TYPE_ADDR
- p.From.Reg = REGSP
- p.From.Offset = int64(objabi.StackGuard)
- p.To.Type = obj.TYPE_REG
- p.To.Reg = REG_R2
- p.Scond = C_SCOND_NE
-
- p = obj.Appendp(p, c.newprog)
- p.As = ASUB
- p.From.Type = obj.TYPE_REG
- p.From.Reg = REG_R1
- p.To.Type = obj.TYPE_REG
- p.To.Reg = REG_R2
- p.Scond = C_SCOND_NE
-
- p = obj.Appendp(p, c.newprog)
- p.As = AMOVW
- p.From.Type = obj.TYPE_ADDR
- p.From.Offset = int64(framesize) + (int64(objabi.StackGuard) - objabi.StackSmall)
- p.To.Type = obj.TYPE_REG
- p.To.Reg = REG_R3
- p.Scond = C_SCOND_NE
-
- p = obj.Appendp(p, c.newprog)
- p.As = ACMP
- p.From.Type = obj.TYPE_REG
- p.From.Reg = REG_R3
- p.Reg = REG_R2
- p.Scond = C_SCOND_NE
- }
-
- // BLS call-to-morestack
- bls := obj.Appendp(p, c.newprog)
- bls.As = ABLS
- bls.To.Type = obj.TYPE_BRANCH
-
- end := c.ctxt.EndUnsafePoint(bls, c.newprog, -1)
-
- var last *obj.Prog
- for last = c.cursym.Func.Text; last.Link != nil; last = last.Link {
- }
-
- // Now we are at the end of the function, but logically
- // we are still in function prologue. We need to fix the
- // SP data and PCDATA.
- spfix := obj.Appendp(last, c.newprog)
- spfix.As = obj.ANOP
- spfix.Spadj = -framesize
-
- pcdata := c.ctxt.EmitEntryStackMap(c.cursym, spfix, c.newprog)
- pcdata = c.ctxt.StartUnsafePoint(pcdata, c.newprog)
-
- // MOVW LR, R3
- movw := obj.Appendp(pcdata, c.newprog)
- movw.As = AMOVW
- movw.From.Type = obj.TYPE_REG
- movw.From.Reg = REGLINK
- movw.To.Type = obj.TYPE_REG
- movw.To.Reg = REG_R3
-
- bls.To.SetTarget(movw)
-
- // BL runtime.morestack
- call := obj.Appendp(movw, c.newprog)
- call.As = obj.ACALL
- call.To.Type = obj.TYPE_BRANCH
- morestack := "runtime.morestack"
- switch {
- case c.cursym.CFunc():
- morestack = "runtime.morestackc"
- case !c.cursym.Func.Text.From.Sym.NeedCtxt():
- morestack = "runtime.morestack_noctxt"
- }
- call.To.Sym = c.ctxt.Lookup(morestack)
-
- pcdata = c.ctxt.EndUnsafePoint(call, c.newprog, -1)
-
- // B start
- b := obj.Appendp(pcdata, c.newprog)
- b.As = obj.AJMP
- b.To.Type = obj.TYPE_BRANCH
- b.To.SetTarget(c.cursym.Func.Text.Link)
- b.Spadj = +framesize
-
- return end
-}
-
-var unaryDst = map[obj.As]bool{
- ASWI: true,
- AWORD: true,
-}
-
-var Linkarm = obj.LinkArch{
- Arch: sys.ArchARM,
- Init: buildop,
- Preprocess: preprocess,
- Assemble: span5,
- Progedit: progedit,
- UnaryDst: unaryDst,
- DWARFRegisters: ARMDWARFRegisters,
-}