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| author | Cuong Manh Le <cuong.manhle.vn@gmail.com> | 2020-04-21 03:47:02 +0700 |
|---|---|---|
| committer | Cuong Manh Le <cuong.manhle.vn@gmail.com> | 2020-04-21 03:45:26 +0000 |
| commit | 7f8fda3c0bfcc832934aa75b4580b4c780e1cb52 (patch) | |
| tree | 2dc5b6cbc36e8a0a1ac0e2ffb1e523e1695d754a /src/cmd/compile/internal/ssa/rewritegeneric.go | |
| parent | 0f14c2a0423ed2416db38ca24edfcb47f46c4e4c (diff) | |
| download | go-7f8fda3c0bfcc832934aa75b4580b4c780e1cb52.tar.gz go-7f8fda3c0bfcc832934aa75b4580b4c780e1cb52.zip | |
cmd/compile: use proper magnitude for (x>>c) & uppermask = 0
This is followup of CL 228860, which rewrite shift rules to use typed
aux. That CL introduced nlz* functions, to refactor left shift rules.
While at it, we realize there's a bug in old rules with both right/left
shift rules, but only fix for left shift rules only.
This CL fixes the bug for right shift rules.
Passes toolstash-check.
Change-Id: Id8f2158b1b66c9e87f3fdeaa7ae3e35dc0666f8b
Reviewed-on: https://go-review.googlesource.com/c/go/+/229137
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
Diffstat (limited to 'src/cmd/compile/internal/ssa/rewritegeneric.go')
| -rw-r--r-- | src/cmd/compile/internal/ssa/rewritegeneric.go | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/src/cmd/compile/internal/ssa/rewritegeneric.go b/src/cmd/compile/internal/ssa/rewritegeneric.go index 214de6448d..6d42f3a36c 100644 --- a/src/cmd/compile/internal/ssa/rewritegeneric.go +++ b/src/cmd/compile/internal/ssa/rewritegeneric.go @@ -1571,7 +1571,7 @@ func rewriteValuegeneric_OpAnd16(v *Value) bool { break } // match: (And16 (Const16 [m]) (Rsh16Ux64 _ (Const64 [c]))) - // cond: c >= int64(64-ntz16(m)) + // cond: c >= int64(16-ntz16(m)) // result: (Const16 [0]) for { for _i0 := 0; _i0 <= 1; _i0, v_0, v_1 = _i0+1, v_1, v_0 { @@ -1588,7 +1588,7 @@ func rewriteValuegeneric_OpAnd16(v *Value) bool { continue } c := auxIntToInt64(v_1_1.AuxInt) - if !(c >= int64(64-ntz16(m))) { + if !(c >= int64(16-ntz16(m))) { continue } v.reset(OpConst16) @@ -1769,7 +1769,7 @@ func rewriteValuegeneric_OpAnd32(v *Value) bool { break } // match: (And32 (Const32 [m]) (Rsh32Ux64 _ (Const64 [c]))) - // cond: c >= int64(64-ntz32(m)) + // cond: c >= int64(32-ntz32(m)) // result: (Const32 [0]) for { for _i0 := 0; _i0 <= 1; _i0, v_0, v_1 = _i0+1, v_1, v_0 { @@ -1786,7 +1786,7 @@ func rewriteValuegeneric_OpAnd32(v *Value) bool { continue } c := auxIntToInt64(v_1_1.AuxInt) - if !(c >= int64(64-ntz32(m))) { + if !(c >= int64(32-ntz32(m))) { continue } v.reset(OpConst32) @@ -2165,7 +2165,7 @@ func rewriteValuegeneric_OpAnd8(v *Value) bool { break } // match: (And8 (Const8 [m]) (Rsh8Ux64 _ (Const64 [c]))) - // cond: c >= int64(64-ntz8(m)) + // cond: c >= int64(8-ntz8(m)) // result: (Const8 [0]) for { for _i0 := 0; _i0 <= 1; _i0, v_0, v_1 = _i0+1, v_1, v_0 { @@ -2182,7 +2182,7 @@ func rewriteValuegeneric_OpAnd8(v *Value) bool { continue } c := auxIntToInt64(v_1_1.AuxInt) - if !(c >= int64(64-ntz8(m))) { + if !(c >= int64(8-ntz8(m))) { continue } v.reset(OpConst8) |