test/codegen: make sure assignment results are used.

Some tests make assignments to an argument without reading it.
With CL 708865, they are treated as dead stores and are removed.
Make sure the results are used.

Fixes #75745.
Fixes #75746.

Change-Id: I05580beb1006505ec1550e5fa245b54dcefd10b9
Reviewed-on: https://go-review.googlesource.com/c/go/+/708916
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Keith Randall <khr@golang.org>

diff --git a/test/codegen/constants.go b/test/codegen/constants.go
index 3ce17d0ad3a65b0318834e471371ad8c83827d2d..0935a9e53a9d8785b1d2cb1d7ffdab635c88156f 100644 (file)
--- a/test/codegen/constants.go
+++ b/test/codegen/constants.go
@@ -7,7 +7,7 @@
 package codegen
 
 // A uint16 or sint16 constant shifted left.
-func shifted16BitConstants(out [64]uint64) {
+func shifted16BitConstants() (out [64]uint64) {
        // ppc64x: "MOVD\t[$]8193,", "SLD\t[$]27,"
        out[0] = 0x0000010008000000
        // ppc64x: "MOVD\t[$]-32767", "SLD\t[$]26,"
@@ -16,10 +16,11 @@ func shifted16BitConstants(out [64]uint64) {
        out[2] = 0xFFFF000000000000
        // ppc64x: "MOVD\t[$]65535", "SLD\t[$]44,"
        out[3] = 0x0FFFF00000000000
+       return
 }
 
 // A contiguous set of 1 bits, potentially wrapping.
-func contiguousMaskConstants(out [64]uint64) {
+func contiguousMaskConstants() (out [64]uint64) {
        // ppc64x: "MOVD\t[$]-1", "RLDC\tR[0-9]+, [$]44, [$]63,"
        out[0] = 0xFFFFF00000000001
        // ppc64x: "MOVD\t[$]-1", "RLDC\tR[0-9]+, [$]43, [$]63,"
@@ -30,4 +31,5 @@ func contiguousMaskConstants(out [64]uint64) {
        // ppc64x/power9: "MOVD\t[$]-1", "RLDC\tR[0-9]+, [$]33, [$]63,"
        // ppc64x/power10: "MOVD\t[$]-8589934591,"
        out[3] = 0xFFFFFFFE00000001
+       return
 }

diff --git a/test/codegen/mathbits.go b/test/codegen/mathbits.go
index ba5387d2c32121cbb9eb03ac9903f507ee83ae43..f8fa374c0af4839f88ba91a4d7e02835b7d1fc58 100644 (file)
--- a/test/codegen/mathbits.go
+++ b/test/codegen/mathbits.go
@@ -731,7 +731,7 @@ func Add64MPanicOnOverflowGT(a, b [2]uint64) [2]uint64 {
 //
 // This is what happened on PPC64 when compiling
 // crypto/internal/edwards25519/field.feMulGeneric.
-func Add64MultipleChains(a, b, c, d [2]uint64) {
+func Add64MultipleChains(a, b, c, d [2]uint64) [2]uint64 {
        var cx, d1, d2 uint64
        a1, a2 := a[0], a[1]
        b1, b2 := b[0], b[1]
@@ -748,6 +748,7 @@ func Add64MultipleChains(a, b, c, d [2]uint64) {
        d2, _ = bits.Add64(c2, d2, cx)
        d[0] = d1
        d[1] = d2
+       return d
 }
 
 // --------------- //