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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:14:23 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:14:23 +0000
commit73df946d56c74384511a194dd01dbe099584fd1a (patch)
treefd0bcea490dd81327ddfbb31e215439672c9a068 /src/cmd/compile/internal/amd64/ggen.go
parentInitial commit. (diff)
downloadgolang-1.16-upstream.tar.xz
golang-1.16-upstream.zip
Adding upstream version 1.16.10.upstream/1.16.10upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/cmd/compile/internal/amd64/ggen.go')
-rw-r--r--src/cmd/compile/internal/amd64/ggen.go137
1 files changed, 137 insertions, 0 deletions
diff --git a/src/cmd/compile/internal/amd64/ggen.go b/src/cmd/compile/internal/amd64/ggen.go
new file mode 100644
index 0000000..0c1456f
--- /dev/null
+++ b/src/cmd/compile/internal/amd64/ggen.go
@@ -0,0 +1,137 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package amd64
+
+import (
+ "cmd/compile/internal/gc"
+ "cmd/internal/obj"
+ "cmd/internal/obj/x86"
+ "cmd/internal/objabi"
+)
+
+// no floating point in note handlers on Plan 9
+var isPlan9 = objabi.GOOS == "plan9"
+
+// DUFFZERO consists of repeated blocks of 4 MOVUPSs + LEAQ,
+// See runtime/mkduff.go.
+const (
+ dzBlocks = 16 // number of MOV/ADD blocks
+ dzBlockLen = 4 // number of clears per block
+ dzBlockSize = 19 // size of instructions in a single block
+ dzMovSize = 4 // size of single MOV instruction w/ offset
+ dzLeaqSize = 4 // size of single LEAQ instruction
+ dzClearStep = 16 // number of bytes cleared by each MOV instruction
+
+ dzClearLen = dzClearStep * dzBlockLen // bytes cleared by one block
+ dzSize = dzBlocks * dzBlockSize
+)
+
+// dzOff returns the offset for a jump into DUFFZERO.
+// b is the number of bytes to zero.
+func dzOff(b int64) int64 {
+ off := int64(dzSize)
+ off -= b / dzClearLen * dzBlockSize
+ tailLen := b % dzClearLen
+ if tailLen >= dzClearStep {
+ off -= dzLeaqSize + dzMovSize*(tailLen/dzClearStep)
+ }
+ return off
+}
+
+// duffzeroDI returns the pre-adjustment to DI for a call to DUFFZERO.
+// b is the number of bytes to zero.
+func dzDI(b int64) int64 {
+ tailLen := b % dzClearLen
+ if tailLen < dzClearStep {
+ return 0
+ }
+ tailSteps := tailLen / dzClearStep
+ return -dzClearStep * (dzBlockLen - tailSteps)
+}
+
+func zerorange(pp *gc.Progs, p *obj.Prog, off, cnt int64, state *uint32) *obj.Prog {
+ const (
+ ax = 1 << iota
+ x0
+ )
+
+ if cnt == 0 {
+ return p
+ }
+
+ if cnt%int64(gc.Widthreg) != 0 {
+ // should only happen with nacl
+ if cnt%int64(gc.Widthptr) != 0 {
+ gc.Fatalf("zerorange count not a multiple of widthptr %d", cnt)
+ }
+ if *state&ax == 0 {
+ p = pp.Appendpp(p, x86.AMOVQ, obj.TYPE_CONST, 0, 0, obj.TYPE_REG, x86.REG_AX, 0)
+ *state |= ax
+ }
+ p = pp.Appendpp(p, x86.AMOVL, obj.TYPE_REG, x86.REG_AX, 0, obj.TYPE_MEM, x86.REG_SP, off)
+ off += int64(gc.Widthptr)
+ cnt -= int64(gc.Widthptr)
+ }
+
+ if cnt == 8 {
+ if *state&ax == 0 {
+ p = pp.Appendpp(p, x86.AMOVQ, obj.TYPE_CONST, 0, 0, obj.TYPE_REG, x86.REG_AX, 0)
+ *state |= ax
+ }
+ p = pp.Appendpp(p, x86.AMOVQ, obj.TYPE_REG, x86.REG_AX, 0, obj.TYPE_MEM, x86.REG_SP, off)
+ } else if !isPlan9 && cnt <= int64(8*gc.Widthreg) {
+ if *state&x0 == 0 {
+ p = pp.Appendpp(p, x86.AXORPS, obj.TYPE_REG, x86.REG_X0, 0, obj.TYPE_REG, x86.REG_X0, 0)
+ *state |= x0
+ }
+
+ for i := int64(0); i < cnt/16; i++ {
+ p = pp.Appendpp(p, x86.AMOVUPS, obj.TYPE_REG, x86.REG_X0, 0, obj.TYPE_MEM, x86.REG_SP, off+i*16)
+ }
+
+ if cnt%16 != 0 {
+ p = pp.Appendpp(p, x86.AMOVUPS, obj.TYPE_REG, x86.REG_X0, 0, obj.TYPE_MEM, x86.REG_SP, off+cnt-int64(16))
+ }
+ } else if !isPlan9 && (cnt <= int64(128*gc.Widthreg)) {
+ if *state&x0 == 0 {
+ p = pp.Appendpp(p, x86.AXORPS, obj.TYPE_REG, x86.REG_X0, 0, obj.TYPE_REG, x86.REG_X0, 0)
+ *state |= x0
+ }
+ p = pp.Appendpp(p, leaptr, obj.TYPE_MEM, x86.REG_SP, off+dzDI(cnt), obj.TYPE_REG, x86.REG_DI, 0)
+ p = pp.Appendpp(p, obj.ADUFFZERO, obj.TYPE_NONE, 0, 0, obj.TYPE_ADDR, 0, dzOff(cnt))
+ p.To.Sym = gc.Duffzero
+
+ if cnt%16 != 0 {
+ p = pp.Appendpp(p, x86.AMOVUPS, obj.TYPE_REG, x86.REG_X0, 0, obj.TYPE_MEM, x86.REG_DI, -int64(8))
+ }
+ } else {
+ if *state&ax == 0 {
+ p = pp.Appendpp(p, x86.AMOVQ, obj.TYPE_CONST, 0, 0, obj.TYPE_REG, x86.REG_AX, 0)
+ *state |= ax
+ }
+
+ p = pp.Appendpp(p, x86.AMOVQ, obj.TYPE_CONST, 0, cnt/int64(gc.Widthreg), obj.TYPE_REG, x86.REG_CX, 0)
+ p = pp.Appendpp(p, leaptr, obj.TYPE_MEM, x86.REG_SP, off, obj.TYPE_REG, x86.REG_DI, 0)
+ p = pp.Appendpp(p, x86.AREP, obj.TYPE_NONE, 0, 0, obj.TYPE_NONE, 0, 0)
+ p = pp.Appendpp(p, x86.ASTOSQ, obj.TYPE_NONE, 0, 0, obj.TYPE_NONE, 0, 0)
+ }
+
+ return p
+}
+
+func ginsnop(pp *gc.Progs) *obj.Prog {
+ // This is a hardware nop (1-byte 0x90) instruction,
+ // even though we describe it as an explicit XCHGL here.
+ // Particularly, this does not zero the high 32 bits
+ // like typical *L opcodes.
+ // (gas assembles "xchg %eax,%eax" to 0x87 0xc0, which
+ // does zero the high 32 bits.)
+ p := pp.Prog(x86.AXCHGL)
+ p.From.Type = obj.TYPE_REG
+ p.From.Reg = x86.REG_AX
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = x86.REG_AX
+ return p
+}