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| author | Robert Griesemer <gri@golang.org> | 2022-04-01 17:02:28 -0700 |
|---|---|---|
| committer | Robert Griesemer <gri@golang.org> | 2022-04-07 17:19:55 +0000 |
| commit | c0bbeb0982403db17bacb1533776fb638cb449ae (patch) | |
| tree | cc1734f83baf56074f35a8210a0b54c5a7857417 /src/cmd/compile/internal/noder/expr.go | |
| parent | 063f4032f5ea8820d265ee1196ef9b8eba02c63f (diff) | |
| download | go-c0bbeb0982403db17bacb1533776fb638cb449ae.tar.xz | |
cmd/compile: adjust types2 shift check to match go/types (cleanup)
With this change, the shift checking code matches the corresponding
go/types code, but for the differences in the internal error reporting,
and call of check.overflow.
The change leads to the recording of an untyped int value if the RHS
of a non-constant shift is an untyped integer value. Adjust the type
in the compiler's irgen accordingly. Add test/shift3.go to verify
behavior.
Change-Id: I20386fcb1d5c48becffdc2203081fb70c08b282d
Reviewed-on: https://go-review.googlesource.com/c/go/+/398236
Trust: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
Trust: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Robert Findley <rfindley@google.com>
Diffstat (limited to 'src/cmd/compile/internal/noder/expr.go')
| -rw-r--r-- | src/cmd/compile/internal/noder/expr.go | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/src/cmd/compile/internal/noder/expr.go b/src/cmd/compile/internal/noder/expr.go index 566abda963..e37e4cd661 100644 --- a/src/cmd/compile/internal/noder/expr.go +++ b/src/cmd/compile/internal/noder/expr.go @@ -6,6 +6,7 @@ package noder import ( "fmt" + "go/constant" "cmd/compile/internal/base" "cmd/compile/internal/ir" @@ -62,6 +63,14 @@ func (g *irgen) expr(expr syntax.Expr) ir.Node { case types2.UntypedNil: // ok; can appear in type switch case clauses // TODO(mdempsky): Handle as part of type switches instead? + case types2.UntypedInt, types2.UntypedFloat, types2.UntypedComplex: + // Untyped rhs of non-constant shift, e.g. x << 1.0. + // If we have a constant value, it must be an int >= 0. + if tv.Value != nil { + s := constant.ToInt(tv.Value) + assert(s.Kind() == constant.Int && constant.Sign(s) >= 0) + } + typ = types2.Typ[types2.Uint] case types2.UntypedBool: typ = types2.Typ[types2.Bool] // expression in "if" or "for" condition case types2.UntypedString: |