mirror of
https://github.com/golang/go
synced 2024-11-11 22:20:22 -07:00
cmd/internal/obj/arm64: fix constant pool size calculation error
The current calculation method of constant pool size is: c.pool.size = -c.pool.size & (funcAlign - 1) c.pool.size += uint32(sz) This doesn't make sense. This CL changes it as: if q.As == ADWORD { c.pool.size = roundUp(c.pool.size, 8) } c.pool.size += uint32(sz) which takes into account the padding size generated by aligning DWORD to 8 bytes. It's unnecessary to set the Pc field in addpool and addpool128 because the Pc value will be reset in function span7, so remove the related lines. Change-Id: I5eb8f259be55a6b97fc2c20958b4a602bffa4f88 Reviewed-on: https://go-review.googlesource.com/c/go/+/298609 Reviewed-by: eric fang <eric.fang@arm.com> Reviewed-by: Cherry Zhang <cherryyz@google.com> Trust: eric fang <eric.fang@arm.com> Run-TryBot: eric fang <eric.fang@arm.com> TryBot-Result: Go Bot <gobot@golang.org>
This commit is contained in:
parent
c819907754
commit
d25476ebb2
@ -1200,19 +1200,16 @@ func (c *ctxt7) flushpool(p *obj.Prog, skip int) {
|
||||
// addpool128 adds a 128-bit constant to literal pool by two consecutive DWORD
|
||||
// instructions, the 128-bit constant is formed by ah.Offset<<64+al.Offset.
|
||||
func (c *ctxt7) addpool128(p *obj.Prog, al, ah *obj.Addr) {
|
||||
lit := al.Offset
|
||||
q := c.newprog()
|
||||
q.As = ADWORD
|
||||
q.To.Type = obj.TYPE_CONST
|
||||
q.To.Offset = lit
|
||||
q.Pc = int64(c.pool.size)
|
||||
q.To.Offset = al.Offset
|
||||
|
||||
lit = ah.Offset
|
||||
t := c.newprog()
|
||||
t.As = ADWORD
|
||||
t.To.Type = obj.TYPE_CONST
|
||||
t.To.Offset = lit
|
||||
t.Pc = int64(c.pool.size + 8)
|
||||
t.To.Offset = ah.Offset
|
||||
|
||||
q.Link = t
|
||||
|
||||
if c.blitrl == nil {
|
||||
@ -1223,6 +1220,7 @@ func (c *ctxt7) addpool128(p *obj.Prog, al, ah *obj.Addr) {
|
||||
}
|
||||
|
||||
c.elitrl = t
|
||||
c.pool.size = roundUp(c.pool.size, 16)
|
||||
c.pool.size += 16
|
||||
p.Pool = q
|
||||
}
|
||||
@ -1267,7 +1265,6 @@ func (c *ctxt7) addpool(p *obj.Prog, a *obj.Addr) {
|
||||
|
||||
q := c.newprog()
|
||||
*q = *t
|
||||
q.Pc = int64(c.pool.size)
|
||||
if c.blitrl == nil {
|
||||
c.blitrl = q
|
||||
c.pool.start = uint32(p.Pc)
|
||||
@ -1275,11 +1272,24 @@ func (c *ctxt7) addpool(p *obj.Prog, a *obj.Addr) {
|
||||
c.elitrl.Link = q
|
||||
}
|
||||
c.elitrl = q
|
||||
c.pool.size = -c.pool.size & (funcAlign - 1)
|
||||
if q.As == ADWORD {
|
||||
// make DWORD 8-byte aligned, this is not required by ISA,
|
||||
// just to avoid performance penalties when loading from
|
||||
// the constant pool across a cache line.
|
||||
c.pool.size = roundUp(c.pool.size, 8)
|
||||
}
|
||||
c.pool.size += uint32(sz)
|
||||
p.Pool = q
|
||||
}
|
||||
|
||||
// roundUp rounds up x to "to".
|
||||
func roundUp(x, to uint32) uint32 {
|
||||
if to == 0 || to&(to-1) != 0 {
|
||||
log.Fatalf("rounded up to a value that is not a power of 2: %d\n", to)
|
||||
}
|
||||
return (x + to - 1) &^ (to - 1)
|
||||
}
|
||||
|
||||
func (c *ctxt7) regoff(a *obj.Addr) uint32 {
|
||||
c.instoffset = 0
|
||||
c.aclass(a)
|
||||
|
Loading…
Reference in New Issue
Block a user