fix shift by uint64 (fixes #418)

neelance · neelance · commit 58495a3f57db · 2016-03-07T13:07:37.000+01:00
diff --git a/compiler/expressions.go b/compiler/expressions.go
@@ -375,10 +375,10 @@ func (c *funcContext) translateExpr(expr ast.Expr) *expression {
 					return c.fixNumber(c.formatExpr("%e %s %e", e.X, op, e.Y), basic)
 				}
 				if e.Op == token.SHR && !isUnsigned(basic) {
-					return c.fixNumber(c.formatParenExpr("%e >> $min(%e, 31)", e.X, e.Y), basic)
+					return c.fixNumber(c.formatParenExpr("%e >> $min(%f, 31)", e.X, e.Y), basic)
 				}
 				y := c.newVariable("y")
-				return c.fixNumber(c.formatExpr("(%s = %s, %s < 32 ? (%e %s %s) : 0)", y, c.translateImplicitConversion(e.Y, types.Typ[types.Uint]), y, e.X, op, y), basic)
+				return c.fixNumber(c.formatExpr("(%s = %f, %s < 32 ? (%e %s %s) : 0)", y, e.Y, y, e.X, op, y), basic)
 			case token.AND, token.OR:
 				if isUnsigned(basic) {
 					return c.formatParenExpr("(%e %t %e) >>> 0", e.X, e.Op, e.Y)
diff --git a/tests/misc_test.go b/tests/misc_test.go
@@ -509,3 +509,12 @@ func TestVendoring(t *testing.T) {
 		t.Fail()
 	}
 }
+
+func TestShift(t *testing.T) {
+	if x := uint(32); uint32(1)<<x != 0 {
+		t.Fail()
+	}
+	if x := uint64(0); uint32(1)<<x != 1 {
+		t.Fail()
+	}
+}

Original file line number	Diff line number	Diff line change
`@@ -375,10 +375,10 @@ func (c funcContext) translateExpr(expr ast.Expr) expression {`
`375`	`375`	`return c.fixNumber(c.formatExpr("%e %s %e", e.X, op, e.Y), basic)`
`376`	`376`	`}`
`377`	`377`	`if e.Op == token.SHR && !isUnsigned(basic) {`
`378`		`- return c.fixNumber(c.formatParenExpr("%e >> $min(%e, 31)", e.X, e.Y), basic)`
	`378`	`+ return c.fixNumber(c.formatParenExpr("%e >> $min(%f, 31)", e.X, e.Y), basic)`
`379`	`379`	`}`
`380`	`380`	`y := c.newVariable("y")`
`381`		`- return c.fixNumber(c.formatExpr("(%s = %s, %s < 32 ? (%e %s %s) : 0)", y, c.translateImplicitConversion(e.Y, types.Typ[types.Uint]), y, e.X, op, y), basic)`
	`381`	`+ return c.fixNumber(c.formatExpr("(%s = %f, %s < 32 ? (%e %s %s) : 0)", y, e.Y, y, e.X, op, y), basic)`
`382`	`382`	`case token.AND, token.OR:`
`383`	`383`	`if isUnsigned(basic) {`
`384`	`384`	`return c.formatParenExpr("(%e %t %e) >>> 0", e.X, e.Op, e.Y)`
Original file line number	Diff line number	Diff line change
`@@ -509,3 +509,12 @@ func TestVendoring(t *testing.T) {`
`509`	`509`	`t.Fail()`
`510`	`510`	`}`
`511`	`511`	`}`
	`512`	`+`
	`513`	`+func TestShift(t *testing.T) {`
	`514`	`+ if x := uint(32); uint32(1)<<x != 0 {`
	`515`	`+ t.Fail()`
	`516`	`+ }`
	`517`	`+ if x := uint64(0); uint32(1)<<x != 1 {`
	`518`	`+ t.Fail()`
	`519`	`+ }`
	`520`	`+}`