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bd8a39b67a
Explcitly block fused multiply-add pattern matching when a cast is used
after the multiplication, for example:
- (a * b) + c // can emit fused multiply-add
- float64(a * b) + c // cannot emit fused multiply-add
float{32,64} and complex{64,128} casts of matching types are now kept
as OCONV operations rather than being replaced with OCONVNOP operations
because they now imply a rounding operation (and therefore aren't a
no-op anymore).
Operations (for example, multiplication) on complex types may utilize
fused multiply-add and -subtract instructions internally. There is no
way to disable this behavior at the moment.
Improves the performance of the floating point implementation of
poly1305:
name old speed new speed delta
64 246MB/s ± 0% 275MB/s ± 0% +11.48% (p=0.000 n=10+8)
1K 312MB/s ± 0% 357MB/s ± 0% +14.41% (p=0.000 n=10+10)
64Unaligned 246MB/s ± 0% 274MB/s ± 0% +11.43% (p=0.000 n=10+10)
1KUnaligned 312MB/s ± 0% 357MB/s ± 0% +14.39% (p=0.000 n=10+8)
Updates #17895.
Change-Id: Ia771d275bb9150d1a598f8cc773444663de5ce16
Reviewed-on: https://go-review.googlesource.com/36963
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
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| .. | ||
| gen | ||
| addressed.go | ||
| append.go | ||
| arith.go | ||
| arithBoundary.go | ||
| arithConst.go | ||
| array.go | ||
| assert.go | ||
| break.go | ||
| chan.go | ||
| closure.go | ||
| cmp.go | ||
| compound.go | ||
| copy.go | ||
| ctl.go | ||
| deferNoReturn.go | ||
| divbyzero.go | ||
| dupLoad.go | ||
| fp.go | ||
| loadstore.go | ||
| map.go | ||
| namedReturn.go | ||
| phi.go | ||
| regalloc.go | ||
| short.go | ||
| slice.go | ||
| sqrt_const.go | ||
| string.go | ||
| unsafe.go | ||
| zero.go | ||