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cmd/compile: use correct type for byteswaps on multi-byte stores

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Use the type of the store for the byteswap, not the type of the
store's value argument.

Normally when we're storing a 16-bit value, the value being stored is
also typed as 16 bits. But sometimes it is typed as something smaller,
usually because it is the result of an upcast from a smaller value,
and that upcast needs no instructions.

If the type of the store's arg is thinner than the type being stored,
and the byteswap'd value uses that thinner type, and the byteswap'd
value needs to be spilled & restored, that spill/restore happens using
the thinner type, which causes us to lose some of the top bits of the
value.

Fixes #59367

Change-Id: If6ce1e8a76f18bf8e9d79871b6caa438bc3cce4d
Reviewed-on: https://go-review.googlesource.com/c/go/+/481395
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
This commit is contained in:
Keith Randall 2023-04-01 10:33:26 -07:00
parent 42866e566a
commit b3bc8620f8
5 changed files with 154 additions and 72 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
src/cmd/compile/internal/ssa/_gen/AMD64.rules
View File

@ -1758,13 +1758,13 @@
x0:(MOVBstore [i-1] {s} p (SHRWconst [8] w) mem))
&& x0.Uses == 1
&& clobber(x0)
=> (MOVWstore [i-1] {s} p (ROLWconst <w.Type> [8] w) mem)
=> (MOVWstore [i-1] {s} p (ROLWconst <typ.UInt16> [8] w) mem)
(MOVBstore [i] {s} p1 w
x0:(MOVBstore [i] {s} p0 (SHRWconst [8] w) mem))
&& x0.Uses == 1
&& sequentialAddresses(p0, p1, 1)
&& clobber(x0)
=> (MOVWstore [i] {s} p0 (ROLWconst <w.Type> [8] w) mem)
=> (MOVWstore [i] {s} p0 (ROLWconst <typ.UInt16> [8] w) mem)
// Combine stores + shifts into bswap and larger (unaligned) stores
(MOVBstore [i] {s} p w
@ -1775,7 +1775,7 @@
&& x1.Uses == 1
&& x2.Uses == 1
&& clobber(x0, x1, x2)
=> (MOVLstore [i-3] {s} p (BSWAPL <w.Type> w) mem)
=> (MOVLstore [i-3] {s} p (BSWAPL <typ.UInt32> w) mem)
(MOVBstore [i] {s} p3 w
x2:(MOVBstore [i] {s} p2 (SHRLconst [8] w)
x1:(MOVBstore [i] {s} p1 (SHRLconst [16] w)
@ -1787,7 +1787,7 @@
&& sequentialAddresses(p1, p2, 1)
&& sequentialAddresses(p2, p3, 1)
&& clobber(x0, x1, x2)
=> (MOVLstore [i] {s} p0 (BSWAPL <w.Type> w) mem)
=> (MOVLstore [i] {s} p0 (BSWAPL <typ.UInt32> w) mem)
(MOVBstore [i] {s} p w
x6:(MOVBstore [i-1] {s} p (SHRQconst [8] w)
@ -1805,7 +1805,7 @@
&& x5.Uses == 1
&& x6.Uses == 1
&& clobber(x0, x1, x2, x3, x4, x5, x6)
=> (MOVQstore [i-7] {s} p (BSWAPQ <w.Type> w) mem)
=> (MOVQstore [i-7] {s} p (BSWAPQ <typ.UInt64> w) mem)
(MOVBstore [i] {s} p7 w
x6:(MOVBstore [i] {s} p6 (SHRQconst [8] w)
x5:(MOVBstore [i] {s} p5 (SHRQconst [16] w)
@ -1829,7 +1829,7 @@
&& sequentialAddresses(p5, p6, 1)
&& sequentialAddresses(p6, p7, 1)
&& clobber(x0, x1, x2, x3, x4, x5, x6)
=> (MOVQstore [i] {s} p0 (BSWAPQ <w.Type> w) mem)
=> (MOVQstore [i] {s} p0 (BSWAPQ <typ.UInt64> w) mem)
// Combine constant stores into larger (unaligned) stores.
(MOVBstoreconst [c] {s} p1 x:(MOVBstoreconst [a] {s} p0 mem))

36
src/cmd/compile/internal/ssa/_gen/ARM64.rules
View File

@ -2688,7 +2688,7 @@
&& x5.Uses == 1
&& x6.Uses == 1
&& clobber(x0, x1, x2, x3, x4, x5, x6)
=> (MOVDstore [i-7] {s} ptr (REV <w.Type> w) mem)
=> (MOVDstore [i-7] {s} ptr (REV <typ.UInt64> w) mem)
(MOVBstore [7] {s} p w
x0:(MOVBstore [6] {s} p (SRLconst [8] w)
x1:(MOVBstore [5] {s} p (SRLconst [16] w)
@ -2708,7 +2708,7 @@
&& (isSamePtr(ptr0, ptr1) && isSamePtr(idx0, idx1) || isSamePtr(ptr0, idx1) && isSamePtr(idx0, ptr1))
&& isSamePtr(p1, p)
&& clobber(x0, x1, x2, x3, x4, x5, x6)
=> (MOVDstoreidx ptr0 idx0 (REV <w.Type> w) mem)
=> (MOVDstoreidx ptr0 idx0 (REV <typ.UInt64> w) mem)
(MOVBstore [i] {s} ptr w
x0:(MOVBstore [i-1] {s} ptr (UBFX [armBFAuxInt(8, 24)] w)
x1:(MOVBstore [i-2] {s} ptr (UBFX [armBFAuxInt(16, 16)] w)
@ -2717,7 +2717,7 @@
&& x1.Uses == 1
&& x2.Uses == 1
&& clobber(x0, x1, x2)
=> (MOVWstore [i-3] {s} ptr (REVW <w.Type> w) mem)
=> (MOVWstore [i-3] {s} ptr (REVW <typ.UInt32> w) mem)
(MOVBstore [3] {s} p w
x0:(MOVBstore [2] {s} p (UBFX [armBFAuxInt(8, 24)] w)
x1:(MOVBstore [1] {s} p1:(ADD ptr1 idx1) (UBFX [armBFAuxInt(16, 16)] w)
@ -2729,7 +2729,7 @@
&& (isSamePtr(ptr0, ptr1) && isSamePtr(idx0, idx1) || isSamePtr(ptr0, idx1) && isSamePtr(idx0, ptr1))
&& isSamePtr(p1, p)
&& clobber(x0, x1, x2)
=> (MOVWstoreidx ptr0 idx0 (REVW <w.Type> w) mem)
=> (MOVWstoreidx ptr0 idx0 (REVW <typ.UInt32> w) mem)
(MOVBstoreidx ptr (ADDconst [3] idx) w
x0:(MOVBstoreidx ptr (ADDconst [2] idx) (UBFX [armBFAuxInt(8, 24)] w)
x1:(MOVBstoreidx ptr (ADDconst [1] idx) (UBFX [armBFAuxInt(16, 16)] w)
@ -2738,7 +2738,7 @@
&& x1.Uses == 1
&& x2.Uses == 1
&& clobber(x0, x1, x2)
=> (MOVWstoreidx ptr idx (REVW <w.Type> w) mem)
=> (MOVWstoreidx ptr idx (REVW <typ.UInt32> w) mem)
(MOVBstoreidx ptr idx w
x0:(MOVBstoreidx ptr (ADDconst [1] idx) (UBFX [armBFAuxInt(8, 24)] w)
x1:(MOVBstoreidx ptr (ADDconst [2] idx) (UBFX [armBFAuxInt(16, 16)] w)
@ -2756,7 +2756,7 @@
&& x1.Uses == 1
&& x2.Uses == 1
&& clobber(x0, x1, x2)
=> (MOVWstore [i-3] {s} ptr (REVW <w.Type> w) mem)
=> (MOVWstore [i-3] {s} ptr (REVW <typ.UInt32> w) mem)
(MOVBstore [3] {s} p w
x0:(MOVBstore [2] {s} p (SRLconst [8] (MOVDreg w))
x1:(MOVBstore [1] {s} p1:(ADD ptr1 idx1) (SRLconst [16] (MOVDreg w))
@ -2768,7 +2768,7 @@
&& (isSamePtr(ptr0, ptr1) && isSamePtr(idx0, idx1) || isSamePtr(ptr0, idx1) && isSamePtr(idx0, ptr1))
&& isSamePtr(p1, p)
&& clobber(x0, x1, x2)
=> (MOVWstoreidx ptr0 idx0 (REVW <w.Type> w) mem)
=> (MOVWstoreidx ptr0 idx0 (REVW <typ.UInt32> w) mem)
(MOVBstore [i] {s} ptr w
x0:(MOVBstore [i-1] {s} ptr (SRLconst [8] w)
x1:(MOVBstore [i-2] {s} ptr (SRLconst [16] w)
@ -2777,7 +2777,7 @@
&& x1.Uses == 1
&& x2.Uses == 1
&& clobber(x0, x1, x2)
=> (MOVWstore [i-3] {s} ptr (REVW <w.Type> w) mem)
=> (MOVWstore [i-3] {s} ptr (REVW <typ.UInt32> w) mem)
(MOVBstore [3] {s} p w
x0:(MOVBstore [2] {s} p (SRLconst [8] w)
x1:(MOVBstore [1] {s} p1:(ADD ptr1 idx1) (SRLconst [16] w)
@ -2789,31 +2789,31 @@
&& (isSamePtr(ptr0, ptr1) && isSamePtr(idx0, idx1) || isSamePtr(ptr0, idx1) && isSamePtr(idx0, ptr1))
&& isSamePtr(p1, p)
&& clobber(x0, x1, x2)
=> (MOVWstoreidx ptr0 idx0 (REVW <w.Type> w) mem)
=> (MOVWstoreidx ptr0 idx0 (REVW <typ.UInt32> w) mem)
(MOVBstore [i] {s} ptr w x:(MOVBstore [i-1] {s} ptr (SRLconst [8] w) mem))
&& x.Uses == 1
&& clobber(x)
=> (MOVHstore [i-1] {s} ptr (REV16W <w.Type> w) mem)
=> (MOVHstore [i-1] {s} ptr (REV16W <typ.UInt16> w) mem)
(MOVBstore [1] {s} (ADD ptr1 idx1) w x:(MOVBstoreidx ptr0 idx0 (SRLconst [8] w) mem))
&& x.Uses == 1
&& s == nil
&& (isSamePtr(ptr0, ptr1) && isSamePtr(idx0, idx1) || isSamePtr(ptr0, idx1) && isSamePtr(idx0, ptr1))
&& clobber(x)
=> (MOVHstoreidx ptr0 idx0 (REV16W <w.Type> w) mem)
=> (MOVHstoreidx ptr0 idx0 (REV16W <typ.UInt16> w) mem)
(MOVBstore [i] {s} ptr w x:(MOVBstore [i-1] {s} ptr (UBFX [armBFAuxInt(8, 8)] w) mem))
&& x.Uses == 1
&& clobber(x)
=> (MOVHstore [i-1] {s} ptr (REV16W <w.Type> w) mem)
=> (MOVHstore [i-1] {s} ptr (REV16W <typ.UInt16> w) mem)
(MOVBstore [1] {s} (ADD ptr1 idx1) w x:(MOVBstoreidx ptr0 idx0 (UBFX [armBFAuxInt(8, 8)] w) mem))
&& x.Uses == 1
&& s == nil
&& (isSamePtr(ptr0, ptr1) && isSamePtr(idx0, idx1) || isSamePtr(ptr0, idx1) && isSamePtr(idx0, ptr1))
&& clobber(x)
=> (MOVHstoreidx ptr0 idx0 (REV16W <w.Type> w) mem)
=> (MOVHstoreidx ptr0 idx0 (REV16W <typ.UInt16> w) mem)
(MOVBstoreidx ptr (ADDconst [1] idx) w x:(MOVBstoreidx ptr idx (UBFX [armBFAuxInt(8, 8)] w) mem))
&& x.Uses == 1
&& clobber(x)
=> (MOVHstoreidx ptr idx (REV16W <w.Type> w) mem)
=> (MOVHstoreidx ptr idx (REV16W <typ.UInt16> w) mem)
(MOVBstoreidx ptr idx w x:(MOVBstoreidx ptr (ADDconst [1] idx) (UBFX [armBFAuxInt(8, 8)] w) mem))
&& x.Uses == 1
&& clobber(x)
@ -2821,23 +2821,23 @@
(MOVBstore [i] {s} ptr w x:(MOVBstore [i-1] {s} ptr (SRLconst [8] (MOVDreg w)) mem))
&& x.Uses == 1
&& clobber(x)
=> (MOVHstore [i-1] {s} ptr (REV16W <w.Type> w) mem)
=> (MOVHstore [i-1] {s} ptr (REV16W <typ.UInt16> w) mem)
(MOVBstore [1] {s} (ADD ptr1 idx1) w x:(MOVBstoreidx ptr0 idx0 (SRLconst [8] (MOVDreg w)) mem))
&& x.Uses == 1
&& s == nil
&& (isSamePtr(ptr0, ptr1) && isSamePtr(idx0, idx1) || isSamePtr(ptr0, idx1) && isSamePtr(idx0, ptr1))
&& clobber(x)
=> (MOVHstoreidx ptr0 idx0 (REV16W <w.Type> w) mem)
=> (MOVHstoreidx ptr0 idx0 (REV16W <typ.UInt16> w) mem)
(MOVBstore [i] {s} ptr w x:(MOVBstore [i-1] {s} ptr (UBFX [armBFAuxInt(8, 24)] w) mem))
&& x.Uses == 1
&& clobber(x)
=> (MOVHstore [i-1] {s} ptr (REV16W <w.Type> w) mem)
=> (MOVHstore [i-1] {s} ptr (REV16W <typ.UInt16> w) mem)
(MOVBstore [1] {s} (ADD ptr1 idx1) w x:(MOVBstoreidx ptr0 idx0 (UBFX [armBFAuxInt(8, 24)] w) mem))
&& x.Uses == 1
&& s == nil
&& (isSamePtr(ptr0, ptr1) && isSamePtr(idx0, idx1) || isSamePtr(ptr0, idx1) && isSamePtr(idx0, ptr1))
&& clobber(x)
=> (MOVHstoreidx ptr0 idx0 (REV16W <w.Type> w) mem)
=> (MOVHstoreidx ptr0 idx0 (REV16W <typ.UInt16> w) mem)
// FP simplification
(FNEGS (FMULS x y)) => (FNMULS x y)

24
src/cmd/compile/internal/ssa/rewriteAMD64.go
View File

@ -10484,7 +10484,7 @@ func rewriteValueAMD64_OpAMD64MOVBstore(v *Value) bool {
}
// match: (MOVBstore [i] {s} p w x0:(MOVBstore [i-1] {s} p (SHRWconst [8] w) mem))
// cond: x0.Uses == 1 && clobber(x0)
// result: (MOVWstore [i-1] {s} p (ROLWconst <w.Type> [8] w) mem)
// result: (MOVWstore [i-1] {s} p (ROLWconst <typ.UInt16> [8] w) mem)
for {
i := auxIntToInt32(v.AuxInt)
s := auxToSym(v.Aux)
@ -10505,7 +10505,7 @@ func rewriteValueAMD64_OpAMD64MOVBstore(v *Value) bool {
v.reset(OpAMD64MOVWstore)
v.AuxInt = int32ToAuxInt(i - 1)
v.Aux = symToAux(s)
v0 := b.NewValue0(x0.Pos, OpAMD64ROLWconst, w.Type)
v0 := b.NewValue0(x0.Pos, OpAMD64ROLWconst, typ.UInt16)
v0.AuxInt = int8ToAuxInt(8)
v0.AddArg(w)
v.AddArg3(p, v0, mem)
@ -10513,7 +10513,7 @@ func rewriteValueAMD64_OpAMD64MOVBstore(v *Value) bool {
}
// match: (MOVBstore [i] {s} p1 w x0:(MOVBstore [i] {s} p0 (SHRWconst [8] w) mem))
// cond: x0.Uses == 1 && sequentialAddresses(p0, p1, 1) && clobber(x0)
// result: (MOVWstore [i] {s} p0 (ROLWconst <w.Type> [8] w) mem)
// result: (MOVWstore [i] {s} p0 (ROLWconst <typ.UInt16> [8] w) mem)
for {
i := auxIntToInt32(v.AuxInt)
s := auxToSym(v.Aux)
@ -10532,7 +10532,7 @@ func rewriteValueAMD64_OpAMD64MOVBstore(v *Value) bool {
v.reset(OpAMD64MOVWstore)
v.AuxInt = int32ToAuxInt(i)
v.Aux = symToAux(s)
v0 := b.NewValue0(x0.Pos, OpAMD64ROLWconst, w.Type)
v0 := b.NewValue0(x0.Pos, OpAMD64ROLWconst, typ.UInt16)
v0.AuxInt = int8ToAuxInt(8)
v0.AddArg(w)
v.AddArg3(p0, v0, mem)
@ -10540,7 +10540,7 @@ func rewriteValueAMD64_OpAMD64MOVBstore(v *Value) bool {
}
// match: (MOVBstore [i] {s} p w x2:(MOVBstore [i-1] {s} p (SHRLconst [8] w) x1:(MOVBstore [i-2] {s} p (SHRLconst [16] w) x0:(MOVBstore [i-3] {s} p (SHRLconst [24] w) mem))))
// cond: x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && clobber(x0, x1, x2)
// result: (MOVLstore [i-3] {s} p (BSWAPL <w.Type> w) mem)
// result: (MOVLstore [i-3] {s} p (BSWAPL <typ.UInt32> w) mem)
for {
i := auxIntToInt32(v.AuxInt)
s := auxToSym(v.Aux)
@ -10585,14 +10585,14 @@ func rewriteValueAMD64_OpAMD64MOVBstore(v *Value) bool {
v.reset(OpAMD64MOVLstore)
v.AuxInt = int32ToAuxInt(i - 3)
v.Aux = symToAux(s)
v0 := b.NewValue0(x0.Pos, OpAMD64BSWAPL, w.Type)
v0 := b.NewValue0(x0.Pos, OpAMD64BSWAPL, typ.UInt32)
v0.AddArg(w)
v.AddArg3(p, v0, mem)
return true
}
// match: (MOVBstore [i] {s} p3 w x2:(MOVBstore [i] {s} p2 (SHRLconst [8] w) x1:(MOVBstore [i] {s} p1 (SHRLconst [16] w) x0:(MOVBstore [i] {s} p0 (SHRLconst [24] w) mem))))
// cond: x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && sequentialAddresses(p0, p1, 1) && sequentialAddresses(p1, p2, 1) && sequentialAddresses(p2, p3, 1) && clobber(x0, x1, x2)
// result: (MOVLstore [i] {s} p0 (BSWAPL <w.Type> w) mem)
// result: (MOVLstore [i] {s} p0 (BSWAPL <typ.UInt32> w) mem)
for {
i := auxIntToInt32(v.AuxInt)
s := auxToSym(v.Aux)
@ -10631,14 +10631,14 @@ func rewriteValueAMD64_OpAMD64MOVBstore(v *Value) bool {
v.reset(OpAMD64MOVLstore)
v.AuxInt = int32ToAuxInt(i)
v.Aux = symToAux(s)
v0 := b.NewValue0(x0.Pos, OpAMD64BSWAPL, w.Type)
v0 := b.NewValue0(x0.Pos, OpAMD64BSWAPL, typ.UInt32)
v0.AddArg(w)
v.AddArg3(p0, v0, mem)
return true
}
// match: (MOVBstore [i] {s} p w x6:(MOVBstore [i-1] {s} p (SHRQconst [8] w) x5:(MOVBstore [i-2] {s} p (SHRQconst [16] w) x4:(MOVBstore [i-3] {s} p (SHRQconst [24] w) x3:(MOVBstore [i-4] {s} p (SHRQconst [32] w) x2:(MOVBstore [i-5] {s} p (SHRQconst [40] w) x1:(MOVBstore [i-6] {s} p (SHRQconst [48] w) x0:(MOVBstore [i-7] {s} p (SHRQconst [56] w) mem))))))))
// cond: x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && x3.Uses == 1 && x4.Uses == 1 && x5.Uses == 1 && x6.Uses == 1 && clobber(x0, x1, x2, x3, x4, x5, x6)
// result: (MOVQstore [i-7] {s} p (BSWAPQ <w.Type> w) mem)
// result: (MOVQstore [i-7] {s} p (BSWAPQ <typ.UInt64> w) mem)
for {
i := auxIntToInt32(v.AuxInt)
s := auxToSym(v.Aux)
@ -10731,14 +10731,14 @@ func rewriteValueAMD64_OpAMD64MOVBstore(v *Value) bool {
v.reset(OpAMD64MOVQstore)
v.AuxInt = int32ToAuxInt(i - 7)
v.Aux = symToAux(s)
v0 := b.NewValue0(x0.Pos, OpAMD64BSWAPQ, w.Type)
v0 := b.NewValue0(x0.Pos, OpAMD64BSWAPQ, typ.UInt64)
v0.AddArg(w)
v.AddArg3(p, v0, mem)
return true
}
// match: (MOVBstore [i] {s} p7 w x6:(MOVBstore [i] {s} p6 (SHRQconst [8] w) x5:(MOVBstore [i] {s} p5 (SHRQconst [16] w) x4:(MOVBstore [i] {s} p4 (SHRQconst [24] w) x3:(MOVBstore [i] {s} p3 (SHRQconst [32] w) x2:(MOVBstore [i] {s} p2 (SHRQconst [40] w) x1:(MOVBstore [i] {s} p1 (SHRQconst [48] w) x0:(MOVBstore [i] {s} p0 (SHRQconst [56] w) mem))))))))
// cond: x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && x3.Uses == 1 && x4.Uses == 1 && x5.Uses == 1 && x6.Uses == 1 && sequentialAddresses(p0, p1, 1) && sequentialAddresses(p1, p2, 1) && sequentialAddresses(p2, p3, 1) && sequentialAddresses(p3, p4, 1) && sequentialAddresses(p4, p5, 1) && sequentialAddresses(p5, p6, 1) && sequentialAddresses(p6, p7, 1) && clobber(x0, x1, x2, x3, x4, x5, x6)
// result: (MOVQstore [i] {s} p0 (BSWAPQ <w.Type> w) mem)
// result: (MOVQstore [i] {s} p0 (BSWAPQ <typ.UInt64> w) mem)
for {
i := auxIntToInt32(v.AuxInt)
s := auxToSym(v.Aux)
@ -10817,7 +10817,7 @@ func rewriteValueAMD64_OpAMD64MOVBstore(v *Value) bool {
v.reset(OpAMD64MOVQstore)
v.AuxInt = int32ToAuxInt(i)
v.Aux = symToAux(s)
v0 := b.NewValue0(x0.Pos, OpAMD64BSWAPQ, w.Type)
v0 := b.NewValue0(x0.Pos, OpAMD64BSWAPQ, typ.UInt64)
v0.AddArg(w)
v.AddArg3(p0, v0, mem)
return true

74
src/cmd/compile/internal/ssa/rewriteARM64.go
View File

@ -8726,6 +8726,7 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
v_0 := v.Args[0]
b := v.Block
config := b.Func.Config
typ := &b.Func.Config.Types
// match: (MOVBstore [off1] {sym} (ADDconst [off2] ptr) val mem)
// cond: is32Bit(int64(off1)+off2) && (ptr.Op != OpSB || !config.ctxt.Flag_dynlink)
// result: (MOVBstore [off1+int32(off2)] {sym} ptr val mem)
@ -9396,7 +9397,7 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
}
// match: (MOVBstore [i] {s} ptr w x0:(MOVBstore [i-1] {s} ptr (SRLconst [8] w) x1:(MOVBstore [i-2] {s} ptr (SRLconst [16] w) x2:(MOVBstore [i-3] {s} ptr (SRLconst [24] w) x3:(MOVBstore [i-4] {s} ptr (SRLconst [32] w) x4:(MOVBstore [i-5] {s} ptr (SRLconst [40] w) x5:(MOVBstore [i-6] {s} ptr (SRLconst [48] w) x6:(MOVBstore [i-7] {s} ptr (SRLconst [56] w) mem))))))))
// cond: x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && x3.Uses == 1 && x4.Uses == 1 && x5.Uses == 1 && x6.Uses == 1 && clobber(x0, x1, x2, x3, x4, x5, x6)
// result: (MOVDstore [i-7] {s} ptr (REV <w.Type> w) mem)
// result: (MOVDstore [i-7] {s} ptr (REV <typ.UInt64> w) mem)
for {
i := auxIntToInt32(v.AuxInt)
s := auxToSym(v.Aux)
@ -9489,14 +9490,14 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
v.reset(OpARM64MOVDstore)
v.AuxInt = int32ToAuxInt(i - 7)
v.Aux = symToAux(s)
v0 := b.NewValue0(x6.Pos, OpARM64REV, w.Type)
v0 := b.NewValue0(x6.Pos, OpARM64REV, typ.UInt64)
v0.AddArg(w)
v.AddArg3(ptr, v0, mem)
return true
}
// match: (MOVBstore [7] {s} p w x0:(MOVBstore [6] {s} p (SRLconst [8] w) x1:(MOVBstore [5] {s} p (SRLconst [16] w) x2:(MOVBstore [4] {s} p (SRLconst [24] w) x3:(MOVBstore [3] {s} p (SRLconst [32] w) x4:(MOVBstore [2] {s} p (SRLconst [40] w) x5:(MOVBstore [1] {s} p1:(ADD ptr1 idx1) (SRLconst [48] w) x6:(MOVBstoreidx ptr0 idx0 (SRLconst [56] w) mem))))))))
// cond: x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && x3.Uses == 1 && x4.Uses == 1 && x5.Uses == 1 && x6.Uses == 1 && s == nil && (isSamePtr(ptr0, ptr1) && isSamePtr(idx0, idx1) || isSamePtr(ptr0, idx1) && isSamePtr(idx0, ptr1)) && isSamePtr(p1, p) && clobber(x0, x1, x2, x3, x4, x5, x6)
// result: (MOVDstoreidx ptr0 idx0 (REV <w.Type> w) mem)
// result: (MOVDstoreidx ptr0 idx0 (REV <typ.UInt64> w) mem)
for {
if auxIntToInt32(v.AuxInt) != 7 {
break
@ -9595,7 +9596,7 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
continue
}
v.reset(OpARM64MOVDstoreidx)
v0 := b.NewValue0(x5.Pos, OpARM64REV, w.Type)
v0 := b.NewValue0(x5.Pos, OpARM64REV, typ.UInt64)
v0.AddArg(w)
v.AddArg4(ptr0, idx0, v0, mem)
return true
@ -9604,7 +9605,7 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
}
// match: (MOVBstore [i] {s} ptr w x0:(MOVBstore [i-1] {s} ptr (UBFX [armBFAuxInt(8, 24)] w) x1:(MOVBstore [i-2] {s} ptr (UBFX [armBFAuxInt(16, 16)] w) x2:(MOVBstore [i-3] {s} ptr (UBFX [armBFAuxInt(24, 8)] w) mem))))
// cond: x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && clobber(x0, x1, x2)
// result: (MOVWstore [i-3] {s} ptr (REVW <w.Type> w) mem)
// result: (MOVWstore [i-3] {s} ptr (REVW <typ.UInt32> w) mem)
for {
i := auxIntToInt32(v.AuxInt)
s := auxToSym(v.Aux)
@ -9649,14 +9650,14 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
v.reset(OpARM64MOVWstore)
v.AuxInt = int32ToAuxInt(i - 3)
v.Aux = symToAux(s)
v0 := b.NewValue0(x2.Pos, OpARM64REVW, w.Type)
v0 := b.NewValue0(x2.Pos, OpARM64REVW, typ.UInt32)
v0.AddArg(w)
v.AddArg3(ptr, v0, mem)
return true
}
// match: (MOVBstore [3] {s} p w x0:(MOVBstore [2] {s} p (UBFX [armBFAuxInt(8, 24)] w) x1:(MOVBstore [1] {s} p1:(ADD ptr1 idx1) (UBFX [armBFAuxInt(16, 16)] w) x2:(MOVBstoreidx ptr0 idx0 (UBFX [armBFAuxInt(24, 8)] w) mem))))
// cond: x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && s == nil && (isSamePtr(ptr0, ptr1) && isSamePtr(idx0, idx1) || isSamePtr(ptr0, idx1) && isSamePtr(idx0, ptr1)) && isSamePtr(p1, p) && clobber(x0, x1, x2)
// result: (MOVWstoreidx ptr0 idx0 (REVW <w.Type> w) mem)
// result: (MOVWstoreidx ptr0 idx0 (REVW <typ.UInt32> w) mem)
for {
if auxIntToInt32(v.AuxInt) != 3 {
break
@ -9707,7 +9708,7 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
continue
}
v.reset(OpARM64MOVWstoreidx)
v0 := b.NewValue0(x1.Pos, OpARM64REVW, w.Type)
v0 := b.NewValue0(x1.Pos, OpARM64REVW, typ.UInt32)
v0.AddArg(w)
v.AddArg4(ptr0, idx0, v0, mem)
return true
@ -9716,7 +9717,7 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
}
// match: (MOVBstore [i] {s} ptr w x0:(MOVBstore [i-1] {s} ptr (SRLconst [8] (MOVDreg w)) x1:(MOVBstore [i-2] {s} ptr (SRLconst [16] (MOVDreg w)) x2:(MOVBstore [i-3] {s} ptr (SRLconst [24] (MOVDreg w)) mem))))
// cond: x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && clobber(x0, x1, x2)
// result: (MOVWstore [i-3] {s} ptr (REVW <w.Type> w) mem)
// result: (MOVWstore [i-3] {s} ptr (REVW <typ.UInt32> w) mem)
for {
i := auxIntToInt32(v.AuxInt)
s := auxToSym(v.Aux)
@ -9773,14 +9774,14 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
v.reset(OpARM64MOVWstore)
v.AuxInt = int32ToAuxInt(i - 3)
v.Aux = symToAux(s)
v0 := b.NewValue0(x2.Pos, OpARM64REVW, w.Type)
v0 := b.NewValue0(x2.Pos, OpARM64REVW, typ.UInt32)
v0.AddArg(w)
v.AddArg3(ptr, v0, mem)
return true
}
// match: (MOVBstore [3] {s} p w x0:(MOVBstore [2] {s} p (SRLconst [8] (MOVDreg w)) x1:(MOVBstore [1] {s} p1:(ADD ptr1 idx1) (SRLconst [16] (MOVDreg w)) x2:(MOVBstoreidx ptr0 idx0 (SRLconst [24] (MOVDreg w)) mem))))
// cond: x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && s == nil && (isSamePtr(ptr0, ptr1) && isSamePtr(idx0, idx1) || isSamePtr(ptr0, idx1) && isSamePtr(idx0, ptr1)) && isSamePtr(p1, p) && clobber(x0, x1, x2)
// result: (MOVWstoreidx ptr0 idx0 (REVW <w.Type> w) mem)
// result: (MOVWstoreidx ptr0 idx0 (REVW <typ.UInt32> w) mem)
for {
if auxIntToInt32(v.AuxInt) != 3 {
break
@ -9843,7 +9844,7 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
continue
}
v.reset(OpARM64MOVWstoreidx)
v0 := b.NewValue0(x1.Pos, OpARM64REVW, w.Type)
v0 := b.NewValue0(x1.Pos, OpARM64REVW, typ.UInt32)
v0.AddArg(w)
v.AddArg4(ptr0, idx0, v0, mem)
return true
@ -9852,7 +9853,7 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
}
// match: (MOVBstore [i] {s} ptr w x0:(MOVBstore [i-1] {s} ptr (SRLconst [8] w) x1:(MOVBstore [i-2] {s} ptr (SRLconst [16] w) x2:(MOVBstore [i-3] {s} ptr (SRLconst [24] w) mem))))
// cond: x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && clobber(x0, x1, x2)
// result: (MOVWstore [i-3] {s} ptr (REVW <w.Type> w) mem)
// result: (MOVWstore [i-3] {s} ptr (REVW <typ.UInt32> w) mem)
for {
i := auxIntToInt32(v.AuxInt)
s := auxToSym(v.Aux)
@ -9897,14 +9898,14 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
v.reset(OpARM64MOVWstore)
v.AuxInt = int32ToAuxInt(i - 3)
v.Aux = symToAux(s)
v0 := b.NewValue0(x2.Pos, OpARM64REVW, w.Type)
v0 := b.NewValue0(x2.Pos, OpARM64REVW, typ.UInt32)
v0.AddArg(w)
v.AddArg3(ptr, v0, mem)
return true
}
// match: (MOVBstore [3] {s} p w x0:(MOVBstore [2] {s} p (SRLconst [8] w) x1:(MOVBstore [1] {s} p1:(ADD ptr1 idx1) (SRLconst [16] w) x2:(MOVBstoreidx ptr0 idx0 (SRLconst [24] w) mem))))
// cond: x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && s == nil && (isSamePtr(ptr0, ptr1) && isSamePtr(idx0, idx1) || isSamePtr(ptr0, idx1) && isSamePtr(idx0, ptr1)) && isSamePtr(p1, p) && clobber(x0, x1, x2)
// result: (MOVWstoreidx ptr0 idx0 (REVW <w.Type> w) mem)
// result: (MOVWstoreidx ptr0 idx0 (REVW <typ.UInt32> w) mem)
for {
if auxIntToInt32(v.AuxInt) != 3 {
break
@ -9955,7 +9956,7 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
continue
}
v.reset(OpARM64MOVWstoreidx)
v0 := b.NewValue0(x1.Pos, OpARM64REVW, w.Type)
v0 := b.NewValue0(x1.Pos, OpARM64REVW, typ.UInt32)
v0.AddArg(w)
v.AddArg4(ptr0, idx0, v0, mem)
return true
@ -9964,7 +9965,7 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
}
// match: (MOVBstore [i] {s} ptr w x:(MOVBstore [i-1] {s} ptr (SRLconst [8] w) mem))
// cond: x.Uses == 1 && clobber(x)
// result: (MOVHstore [i-1] {s} ptr (REV16W <w.Type> w) mem)
// result: (MOVHstore [i-1] {s} ptr (REV16W <typ.UInt16> w) mem)
for {
i := auxIntToInt32(v.AuxInt)
s := auxToSym(v.Aux)
@ -9985,14 +9986,14 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
v.reset(OpARM64MOVHstore)
v.AuxInt = int32ToAuxInt(i - 1)
v.Aux = symToAux(s)
v0 := b.NewValue0(x.Pos, OpARM64REV16W, w.Type)
v0 := b.NewValue0(x.Pos, OpARM64REV16W, typ.UInt16)
v0.AddArg(w)
v.AddArg3(ptr, v0, mem)
return true
}
// match: (MOVBstore [1] {s} (ADD ptr1 idx1) w x:(MOVBstoreidx ptr0 idx0 (SRLconst [8] w) mem))
// cond: x.Uses == 1 && s == nil && (isSamePtr(ptr0, ptr1) && isSamePtr(idx0, idx1) || isSamePtr(ptr0, idx1) && isSamePtr(idx0, ptr1)) && clobber(x)
// result: (MOVHstoreidx ptr0 idx0 (REV16W <w.Type> w) mem)
// result: (MOVHstoreidx ptr0 idx0 (REV16W <typ.UInt16> w) mem)
for {
if auxIntToInt32(v.AuxInt) != 1 {
break
@ -10020,7 +10021,7 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
continue
}
v.reset(OpARM64MOVHstoreidx)
v0 := b.NewValue0(v.Pos, OpARM64REV16W, w.Type)
v0 := b.NewValue0(v.Pos, OpARM64REV16W, typ.UInt16)
v0.AddArg(w)
v.AddArg4(ptr0, idx0, v0, mem)
return true
@ -10029,7 +10030,7 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
}
// match: (MOVBstore [i] {s} ptr w x:(MOVBstore [i-1] {s} ptr (UBFX [armBFAuxInt(8, 8)] w) mem))
// cond: x.Uses == 1 && clobber(x)
// result: (MOVHstore [i-1] {s} ptr (REV16W <w.Type> w) mem)
// result: (MOVHstore [i-1] {s} ptr (REV16W <typ.UInt16> w) mem)
for {
i := auxIntToInt32(v.AuxInt)
s := auxToSym(v.Aux)
@ -10050,14 +10051,14 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
v.reset(OpARM64MOVHstore)
v.AuxInt = int32ToAuxInt(i - 1)
v.Aux = symToAux(s)
v0 := b.NewValue0(x.Pos, OpARM64REV16W, w.Type)
v0 := b.NewValue0(x.Pos, OpARM64REV16W, typ.UInt16)
v0.AddArg(w)
v.AddArg3(ptr, v0, mem)
return true
}
// match: (MOVBstore [1] {s} (ADD ptr1 idx1) w x:(MOVBstoreidx ptr0 idx0 (UBFX [armBFAuxInt(8, 8)] w) mem))
// cond: x.Uses == 1 && s == nil && (isSamePtr(ptr0, ptr1) && isSamePtr(idx0, idx1) || isSamePtr(ptr0, idx1) && isSamePtr(idx0, ptr1)) && clobber(x)
// result: (MOVHstoreidx ptr0 idx0 (REV16W <w.Type> w) mem)
// result: (MOVHstoreidx ptr0 idx0 (REV16W <typ.UInt16> w) mem)
for {
if auxIntToInt32(v.AuxInt) != 1 {
break
@ -10085,7 +10086,7 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
continue
}
v.reset(OpARM64MOVHstoreidx)
v0 := b.NewValue0(v.Pos, OpARM64REV16W, w.Type)
v0 := b.NewValue0(v.Pos, OpARM64REV16W, typ.UInt16)
v0.AddArg(w)
v.AddArg4(ptr0, idx0, v0, mem)
return true
@ -10094,7 +10095,7 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
}
// match: (MOVBstore [i] {s} ptr w x:(MOVBstore [i-1] {s} ptr (SRLconst [8] (MOVDreg w)) mem))
// cond: x.Uses == 1 && clobber(x)
// result: (MOVHstore [i-1] {s} ptr (REV16W <w.Type> w) mem)
// result: (MOVHstore [i-1] {s} ptr (REV16W <typ.UInt16> w) mem)
for {
i := auxIntToInt32(v.AuxInt)
s := auxToSym(v.Aux)
@ -10119,14 +10120,14 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
v.reset(OpARM64MOVHstore)
v.AuxInt = int32ToAuxInt(i - 1)
v.Aux = symToAux(s)
v0 := b.NewValue0(x.Pos, OpARM64REV16W, w.Type)
v0 := b.NewValue0(x.Pos, OpARM64REV16W, typ.UInt16)
v0.AddArg(w)
v.AddArg3(ptr, v0, mem)
return true
}
// match: (MOVBstore [1] {s} (ADD ptr1 idx1) w x:(MOVBstoreidx ptr0 idx0 (SRLconst [8] (MOVDreg w)) mem))
// cond: x.Uses == 1 && s == nil && (isSamePtr(ptr0, ptr1) && isSamePtr(idx0, idx1) || isSamePtr(ptr0, idx1) && isSamePtr(idx0, ptr1)) && clobber(x)
// result: (MOVHstoreidx ptr0 idx0 (REV16W <w.Type> w) mem)
// result: (MOVHstoreidx ptr0 idx0 (REV16W <typ.UInt16> w) mem)
for {
if auxIntToInt32(v.AuxInt) != 1 {
break
@ -10158,7 +10159,7 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
continue
}
v.reset(OpARM64MOVHstoreidx)
v0 := b.NewValue0(v.Pos, OpARM64REV16W, w.Type)
v0 := b.NewValue0(v.Pos, OpARM64REV16W, typ.UInt16)
v0.AddArg(w)
v.AddArg4(ptr0, idx0, v0, mem)
return true
@ -10167,7 +10168,7 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
}
// match: (MOVBstore [i] {s} ptr w x:(MOVBstore [i-1] {s} ptr (UBFX [armBFAuxInt(8, 24)] w) mem))
// cond: x.Uses == 1 && clobber(x)
// result: (MOVHstore [i-1] {s} ptr (REV16W <w.Type> w) mem)
// result: (MOVHstore [i-1] {s} ptr (REV16W <typ.UInt16> w) mem)
for {
i := auxIntToInt32(v.AuxInt)
s := auxToSym(v.Aux)
@ -10188,14 +10189,14 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
v.reset(OpARM64MOVHstore)
v.AuxInt = int32ToAuxInt(i - 1)
v.Aux = symToAux(s)
v0 := b.NewValue0(x.Pos, OpARM64REV16W, w.Type)
v0 := b.NewValue0(x.Pos, OpARM64REV16W, typ.UInt16)
v0.AddArg(w)
v.AddArg3(ptr, v0, mem)
return true
}
// match: (MOVBstore [1] {s} (ADD ptr1 idx1) w x:(MOVBstoreidx ptr0 idx0 (UBFX [armBFAuxInt(8, 24)] w) mem))
// cond: x.Uses == 1 && s == nil && (isSamePtr(ptr0, ptr1) && isSamePtr(idx0, idx1) || isSamePtr(ptr0, idx1) && isSamePtr(idx0, ptr1)) && clobber(x)
// result: (MOVHstoreidx ptr0 idx0 (REV16W <w.Type> w) mem)
// result: (MOVHstoreidx ptr0 idx0 (REV16W <typ.UInt16> w) mem)
for {
if auxIntToInt32(v.AuxInt) != 1 {
break
@ -10223,7 +10224,7 @@ func rewriteValueARM64_OpARM64MOVBstore(v *Value) bool {
continue
}
v.reset(OpARM64MOVHstoreidx)
v0 := b.NewValue0(v.Pos, OpARM64REV16W, w.Type)
v0 := b.NewValue0(v.Pos, OpARM64REV16W, typ.UInt16)
v0.AddArg(w)
v.AddArg4(ptr0, idx0, v0, mem)
return true
@ -10238,6 +10239,7 @@ func rewriteValueARM64_OpARM64MOVBstoreidx(v *Value) bool {
v_1 := v.Args[1]
v_0 := v.Args[0]
b := v.Block
typ := &b.Func.Config.Types
// match: (MOVBstoreidx ptr (MOVDconst [c]) val mem)
// cond: is32Bit(c)
// result: (MOVBstore [int32(c)] ptr val mem)
@ -10400,7 +10402,7 @@ func rewriteValueARM64_OpARM64MOVBstoreidx(v *Value) bool {
}
// match: (MOVBstoreidx ptr (ADDconst [3] idx) w x0:(MOVBstoreidx ptr (ADDconst [2] idx) (UBFX [armBFAuxInt(8, 24)] w) x1:(MOVBstoreidx ptr (ADDconst [1] idx) (UBFX [armBFAuxInt(16, 16)] w) x2:(MOVBstoreidx ptr idx (UBFX [armBFAuxInt(24, 8)] w) mem))))
// cond: x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && clobber(x0, x1, x2)
// result: (MOVWstoreidx ptr idx (REVW <w.Type> w) mem)
// result: (MOVWstoreidx ptr idx (REVW <typ.UInt32> w) mem)
for {
ptr := v_0
if v_1.Op != OpARM64ADDconst || auxIntToInt64(v_1.AuxInt) != 3 {
@ -10453,7 +10455,7 @@ func rewriteValueARM64_OpARM64MOVBstoreidx(v *Value) bool {
break
}
v.reset(OpARM64MOVWstoreidx)
v0 := b.NewValue0(v.Pos, OpARM64REVW, w.Type)
v0 := b.NewValue0(v.Pos, OpARM64REVW, typ.UInt32)
v0.AddArg(w)
v.AddArg4(ptr, idx, v0, mem)
return true
@ -10519,7 +10521,7 @@ func rewriteValueARM64_OpARM64MOVBstoreidx(v *Value) bool {
}
// match: (MOVBstoreidx ptr (ADDconst [1] idx) w x:(MOVBstoreidx ptr idx (UBFX [armBFAuxInt(8, 8)] w) mem))
// cond: x.Uses == 1 && clobber(x)
// result: (MOVHstoreidx ptr idx (REV16W <w.Type> w) mem)
// result: (MOVHstoreidx ptr idx (REV16W <typ.UInt16> w) mem)
for {
ptr := v_0
if v_1.Op != OpARM64ADDconst || auxIntToInt64(v_1.AuxInt) != 1 {
@ -10540,7 +10542,7 @@ func rewriteValueARM64_OpARM64MOVBstoreidx(v *Value) bool {
break
}
v.reset(OpARM64MOVHstoreidx)
v0 := b.NewValue0(v.Pos, OpARM64REV16W, w.Type)
v0 := b.NewValue0(v.Pos, OpARM64REV16W, typ.UInt16)
v0.AddArg(w)
v.AddArg4(ptr, idx, v0, mem)
return true

80
test/fixedbugs/issue59367.go Normal file
View File

@ -0,0 +1,80 @@
// run
// Copyright 2023 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 main
func main() {
var b [8]byte
one := uint8(1)
f16(&one, b[:2])
if b[1] != 1 {
println("2-byte value lost")
}
f32(&one, b[:4])
if b[3] != 1 {
println("4-byte value lost")
}
f64(&one, b[:8])
if b[7] != 1 {
println("8-byte value lost")
}
}
//go:noinline
func f16(p *uint8, b []byte) {
_ = b[1] // bounds check
x := *p // load a byte
y := uint16(x) // zero extend to 16 bits
b[0] = byte(y >> 8) // compute ROLW
b[1] = byte(y)
nop() // spill/restore ROLW
b[0] = byte(y >> 8) // use ROLW
b[1] = byte(y)
}
//go:noinline
func f32(p *uint8, b []byte) {
_ = b[3] // bounds check
x := *p // load a byte
y := uint32(x) // zero extend to 32 bits
b[0] = byte(y >> 24) // compute ROLL
b[1] = byte(y >> 16)
b[2] = byte(y >> 8)
b[3] = byte(y)
nop() // spill/restore ROLL
b[0] = byte(y >> 24) // use ROLL
b[1] = byte(y >> 16)
b[2] = byte(y >> 8)
b[3] = byte(y)
}
//go:noinline
func f64(p *uint8, b []byte) {
_ = b[7] // bounds check
x := *p // load a byte
y := uint64(x) // zero extend to 64 bits
b[0] = byte(y >> 56) // compute ROLQ
b[1] = byte(y >> 48)
b[2] = byte(y >> 40)
b[3] = byte(y >> 32)
b[4] = byte(y >> 24)
b[5] = byte(y >> 16)
b[6] = byte(y >> 8)
b[7] = byte(y)
nop() // spill/restore ROLQ
b[0] = byte(y >> 56) // use ROLQ
b[1] = byte(y >> 48)
b[2] = byte(y >> 40)
b[3] = byte(y >> 32)
b[4] = byte(y >> 24)
b[5] = byte(y >> 16)
b[6] = byte(y >> 8)
b[7] = byte(y)
}
//go:noinline
func nop() {
}