math: adjust compilation flags, use them when testing

We were using special compilation flags for the math package, but we
    weren't using them when testing.  That meant that our tests were not
    checking the real code we were providing.  Fix that.
    
    Fixing that revealed that we were not using a good set of flags, or at
    least were not using flags that let the tests pass.  Adjust the flags
    to stop using -funsafe-math-optimizations on x86.  Instead always use
    -ffp-contract=off -fno-math-errno -fno-trapping-math for all targets.
    
    Fixes golang/go#23647
    
    Reviewed-on: https://go-review.googlesource.com/91355

From-SVN: r257312
This commit is contained in:
Ian Lance Taylor 2018-02-01 21:05:20 +00:00
parent d15f0fa7f9
commit 28f3c8143b
5 changed files with 12 additions and 13 deletions

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@ -1138,6 +1138,7 @@ $(foreach package,$(GOTOOL_PACKAGES),$(eval $(call PACKAGE_template,$(package)))
# Pass -ffp-contract=off, or 386-specific options, when building the # Pass -ffp-contract=off, or 386-specific options, when building the
# math package. MATH_FLAG is defined in configure.ac. # math package. MATH_FLAG is defined in configure.ac.
math_lo_GOCFLAGS = $(MATH_FLAG) math_lo_GOCFLAGS = $(MATH_FLAG)
math_check_GOCFLAGS = $(MATH_FLAG)
# Add the generated file runtime_sysinfo.go to the runtime package. # Add the generated file runtime_sysinfo.go to the runtime package.
extra_go_files_runtime = runtime_sysinfo.go sigtab.go extra_go_files_runtime = runtime_sysinfo.go sigtab.go

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@ -1175,6 +1175,7 @@ CHECK_DEPS = $(toolexeclibgo_DATA) $(toolexeclibgoarchive_DATA) \
# Pass -ffp-contract=off, or 386-specific options, when building the # Pass -ffp-contract=off, or 386-specific options, when building the
# math package. MATH_FLAG is defined in configure.ac. # math package. MATH_FLAG is defined in configure.ac.
math_lo_GOCFLAGS = $(MATH_FLAG) math_lo_GOCFLAGS = $(MATH_FLAG)
math_check_GOCFLAGS = $(MATH_FLAG)
# Add the generated file runtime_sysinfo.go to the runtime package. # Add the generated file runtime_sysinfo.go to the runtime package.
extra_go_files_runtime = runtime_sysinfo.go sigtab.go extra_go_files_runtime = runtime_sysinfo.go sigtab.go

5
libgo/configure vendored
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@ -15076,10 +15076,9 @@ fi
$as_echo "$libgo_cv_c_fancymath" >&6; } $as_echo "$libgo_cv_c_fancymath" >&6; }
MATH_FLAG= MATH_FLAG=
if test "$libgo_cv_c_fancymath" = yes; then if test "$libgo_cv_c_fancymath" = yes; then
MATH_FLAG="-mfancy-math-387 -funsafe-math-optimizations -fno-math-errno" MATH_FLAG="-mfancy-math-387"
else
MATH_FLAG="-ffp-contract=off"
fi fi
MATH_FLAG="${MATH_FLAG} -ffp-contract=off -fno-math-errno -fno-trapping-math"
CFLAGS_hold=$CFLAGS CFLAGS_hold=$CFLAGS

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@ -649,8 +649,7 @@ fi
AC_SUBST(STRINGOPS_FLAG) AC_SUBST(STRINGOPS_FLAG)
dnl For x86 we want to compile the math library with -mfancy-math-387 dnl For x86 we want to compile the math library with -mfancy-math-387
dnl -funsafe-math-optimizations so that we can use the builtin dnl so that we can use the builtin instructions directly.
dnl instructions directly.
AC_CACHE_CHECK([whether compiler supports -mfancy-math-387], AC_CACHE_CHECK([whether compiler supports -mfancy-math-387],
[libgo_cv_c_fancymath], [libgo_cv_c_fancymath],
[CFLAGS_hold=$CFLAGS [CFLAGS_hold=$CFLAGS
@ -661,10 +660,9 @@ AC_COMPILE_IFELSE([int i;],
CFLAGS=$CFLAGS_hold]) CFLAGS=$CFLAGS_hold])
MATH_FLAG= MATH_FLAG=
if test "$libgo_cv_c_fancymath" = yes; then if test "$libgo_cv_c_fancymath" = yes; then
MATH_FLAG="-mfancy-math-387 -funsafe-math-optimizations -fno-math-errno" MATH_FLAG="-mfancy-math-387"
else
MATH_FLAG="-ffp-contract=off"
fi fi
MATH_FLAG="${MATH_FLAG} -ffp-contract=off -fno-math-errno -fno-trapping-math"
AC_SUBST(MATH_FLAG) AC_SUBST(MATH_FLAG)
CFLAGS_hold=$CFLAGS CFLAGS_hold=$CFLAGS

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@ -128,7 +128,7 @@ var cbrt = []float64{
var ceil = []float64{ var ceil = []float64{
5.0000000000000000e+00, 5.0000000000000000e+00,
8.0000000000000000e+00, 8.0000000000000000e+00,
0.0000000000000000e+00, Copysign(0, -1),
-5.0000000000000000e+00, -5.0000000000000000e+00,
1.0000000000000000e+01, 1.0000000000000000e+01,
3.0000000000000000e+00, 3.0000000000000000e+00,
@ -644,7 +644,7 @@ var tanh = []float64{
var trunc = []float64{ var trunc = []float64{
4.0000000000000000e+00, 4.0000000000000000e+00,
7.0000000000000000e+00, 7.0000000000000000e+00,
-0.0000000000000000e+00, Copysign(0, -1),
-5.0000000000000000e+00, -5.0000000000000000e+00,
9.0000000000000000e+00, 9.0000000000000000e+00,
2.0000000000000000e+00, 2.0000000000000000e+00,
@ -2134,7 +2134,7 @@ func TestCbrt(t *testing.T) {
func TestCeil(t *testing.T) { func TestCeil(t *testing.T) {
for i := 0; i < len(vf); i++ { for i := 0; i < len(vf); i++ {
if f := Ceil(vf[i]); ceil[i] != f { if f := Ceil(vf[i]); !alike(ceil[i], f) {
t.Errorf("Ceil(%g) = %g, want %g", vf[i], f, ceil[i]) t.Errorf("Ceil(%g) = %g, want %g", vf[i], f, ceil[i])
} }
} }
@ -2361,7 +2361,7 @@ func TestDim(t *testing.T) {
func TestFloor(t *testing.T) { func TestFloor(t *testing.T) {
for i := 0; i < len(vf); i++ { for i := 0; i < len(vf); i++ {
if f := Floor(vf[i]); floor[i] != f { if f := Floor(vf[i]); !alike(floor[i], f) {
t.Errorf("Floor(%g) = %g, want %g", vf[i], f, floor[i]) t.Errorf("Floor(%g) = %g, want %g", vf[i], f, floor[i])
} }
} }
@ -2884,7 +2884,7 @@ func TestTanh(t *testing.T) {
func TestTrunc(t *testing.T) { func TestTrunc(t *testing.T) {
for i := 0; i < len(vf); i++ { for i := 0; i < len(vf); i++ {
if f := Trunc(vf[i]); trunc[i] != f { if f := Trunc(vf[i]); !alike(trunc[i], f) {
t.Errorf("Trunc(%g) = %g, want %g", vf[i], f, trunc[i]) t.Errorf("Trunc(%g) = %g, want %g", vf[i], f, trunc[i])
} }
} }