[dev.ssa] cmd/compile: minor cleanup
Cull dead code. Add TODOs.
Change-Id: I81d24371de47f5a27d3a3a0ec0ef5baaf6814c06
Reviewed-on: https://go-review.googlesource.com/12659
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/src/cmd/compile/internal/gc/ssa.go b/src/cmd/compile/internal/gc/ssa.go
index b883179..e9f99b1 100644
--- a/src/cmd/compile/internal/gc/ssa.go
+++ b/src/cmd/compile/internal/gc/ssa.go
@@ -1114,6 +1114,8 @@
// nilCheck generates nil pointer checking code.
// Starts a new block on return.
+// Used only for automatically inserted nil checks,
+// not for user code like 'x != nil'.
func (s *state) nilCheck(ptr *ssa.Value) {
c := s.newValue1(ssa.OpIsNonNil, ssa.TypeBool, ptr)
b := s.endBlock()
@@ -1466,7 +1468,6 @@
p.From.Reg = x
p.To.Type = obj.TYPE_REG
p.To.Reg = r
- x = r
}
p := Prog(x86.ASUBQ)
p.From.Type = obj.TYPE_CONST
@@ -1485,7 +1486,6 @@
p.From.Reg = x
p.To.Type = obj.TYPE_REG
p.To.Reg = r
- x = r
}
p := Prog(v.Op.Asm())
p.From.Type = obj.TYPE_REG
@@ -1501,7 +1501,6 @@
p.From.Reg = x
p.To.Type = obj.TYPE_REG
p.To.Reg = r
- x = r
}
p := Prog(v.Op.Asm())
p.From.Type = obj.TYPE_CONST
