[libcxx-commits] [libcxx] [libcxx][test][z/OS] Fix hermite.pass.cpp for HEX float (PR #101019)
Zibi Sarbinowski via libcxx-commits
libcxx-commits at lists.llvm.org
Fri Aug 2 13:32:51 PDT 2024
https://github.com/zibi2 updated https://github.com/llvm/llvm-project/pull/101019
>From 5df433b4ea5e657079e5d5e7305dc06b0331beeb Mon Sep 17 00:00:00 2001
From: Zbigniew Sarbinowski <zibi at ca.ibm.com>
Date: Mon, 29 Jul 2024 14:01:36 +0000
Subject: [PATCH 1/5] Fix hermite.pass.cpp for HEX float on z/OS
---
libcxx/test/std/numerics/c.math/hermite.pass.cpp | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/libcxx/test/std/numerics/c.math/hermite.pass.cpp b/libcxx/test/std/numerics/c.math/hermite.pass.cpp
index 08fbd5c3283c1..fb702369ad036 100644
--- a/libcxx/test/std/numerics/c.math/hermite.pass.cpp
+++ b/libcxx/test/std/numerics/c.math/hermite.pass.cpp
@@ -26,7 +26,12 @@
#include "type_algorithms.h"
-inline constexpr unsigned g_max_n = 128;
+inline constexpr unsigned g_max_n =
+#if !(defined(__MVS__) && !defined(__BFP__))
+ 128;
+#else
+ 39;
+#endif
template <class T>
std::array<T, 11> sample_points() {
@@ -203,6 +208,7 @@ std::vector<T> get_roots(unsigned n) {
template <class Real>
void test() {
+#if !(defined(__MVS__) && !defined(__BFP__))
{ // checks if NaNs are reported correctly (i.e. output == input for input == NaN)
using nl = std::numeric_limits<Real>;
for (Real NaN : {nl::quiet_NaN(), nl::signaling_NaN()})
@@ -215,6 +221,7 @@ void test() {
for (unsigned n = 0; n < g_max_n; ++n)
assert(!std::isnan(std::hermite(n, x)));
}
+#endif
{ // checks std::hermite(n, x) for n=0..5 against analytic polynoms
const auto h0 = [](Real) -> Real { return 1; };
@@ -289,6 +296,7 @@ void test() {
}
}
+#if !(defined(__MVS__) && !defined(__BFP__))
{ // check input infinity is handled correctly
Real inf = std::numeric_limits<Real>::infinity();
for (unsigned n = 1; n < g_max_n; ++n) {
@@ -316,6 +324,7 @@ void test() {
}
}
}
+#endif
}
struct TestFloat {
>From 75025ad1b8fd35537bd3fa5e862fefe76b2fd446 Mon Sep 17 00:00:00 2001
From: Zbigniew Sarbinowski <zibi at ca.ibm.com>
Date: Mon, 29 Jul 2024 14:51:25 +0000
Subject: [PATCH 2/5] clang-format change
---
libcxx/test/std/numerics/c.math/hermite.pass.cpp | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/libcxx/test/std/numerics/c.math/hermite.pass.cpp b/libcxx/test/std/numerics/c.math/hermite.pass.cpp
index fb702369ad036..2da2b0b5224af 100644
--- a/libcxx/test/std/numerics/c.math/hermite.pass.cpp
+++ b/libcxx/test/std/numerics/c.math/hermite.pass.cpp
@@ -28,9 +28,9 @@
inline constexpr unsigned g_max_n =
#if !(defined(__MVS__) && !defined(__BFP__))
- 128;
+ 128;
#else
- 39;
+ 39;
#endif
template <class T>
>From b4ece9122d33080c511dd44aca053d41d2c3ad9c Mon Sep 17 00:00:00 2001
From: Zbigniew Sarbinowski <zibi at ca.ibm.com>
Date: Wed, 31 Jul 2024 21:35:10 +0000
Subject: [PATCH 3/5] eliminating #if directives and code formatting
---
.../test/std/numerics/c.math/hermite.pass.cpp | 49 ++++++++++---------
1 file changed, 26 insertions(+), 23 deletions(-)
diff --git a/libcxx/test/std/numerics/c.math/hermite.pass.cpp b/libcxx/test/std/numerics/c.math/hermite.pass.cpp
index 2da2b0b5224af..28bf27cafc3dd 100644
--- a/libcxx/test/std/numerics/c.math/hermite.pass.cpp
+++ b/libcxx/test/std/numerics/c.math/hermite.pass.cpp
@@ -26,12 +26,13 @@
#include "type_algorithms.h"
-inline constexpr unsigned g_max_n =
-#if !(defined(__MVS__) && !defined(__BFP__))
- 128;
-#else
- 39;
-#endif
+template <class Real>
+constexpr unsigned get_maximal_order() {
+ if constexpr (std::numeric_limits<Real>::max_exponent10 < std::numeric_limits<Real>::max_exponent)
+ return 128;
+ else
+ return 39;
+}
template <class T>
std::array<T, 11> sample_points() {
@@ -208,20 +209,23 @@ std::vector<T> get_roots(unsigned n) {
template <class Real>
void test() {
-#if !(defined(__MVS__) && !defined(__BFP__))
- { // checks if NaNs are reported correctly (i.e. output == input for input == NaN)
+ if constexpr (
+ std::numeric_limits<Real>::has_quiet_NaN &&
+ std::numeric_limits<
+ Real>::has_signaling_NaN) { // checks if NaNs are reported correctly (i.e. output == input for input == NaN)
using nl = std::numeric_limits<Real>;
for (Real NaN : {nl::quiet_NaN(), nl::signaling_NaN()})
- for (unsigned n = 0; n < g_max_n; ++n)
+ for (unsigned n = 0; n < get_maximal_order<Real>(); ++n)
assert(std::isnan(std::hermite(n, NaN)));
}
- { // simple sample points for n=0..127 should not produce NaNs.
+ if constexpr (std::numeric_limits<Real>::has_quiet_NaN &&
+ std::numeric_limits<
+ Real>::has_signaling_NaN) { // simple sample points for n=0..127 should not produce NaNs.
for (Real x : sample_points<Real>())
- for (unsigned n = 0; n < g_max_n; ++n)
+ for (unsigned n = 0; n < get_maximal_order<Real>(); ++n)
assert(!std::isnan(std::hermite(n, x)));
}
-#endif
{ // checks std::hermite(n, x) for n=0..5 against analytic polynoms
const auto h0 = [](Real) -> Real { return 1; };
@@ -244,21 +248,21 @@ void test() {
{ // checks std::hermitef for bitwise equality with std::hermite(unsigned, float)
if constexpr (std::is_same_v<Real, float>)
- for (unsigned n = 0; n < g_max_n; ++n)
+ for (unsigned n = 0; n < get_maximal_order<Real>(); ++n)
for (float x : sample_points<float>())
assert(std::hermite(n, x) == std::hermitef(n, x));
}
{ // checks std::hermitel for bitwise equality with std::hermite(unsigned, long double)
if constexpr (std::is_same_v<Real, long double>)
- for (unsigned n = 0; n < g_max_n; ++n)
+ for (unsigned n = 0; n < get_maximal_order<Real>(); ++n)
for (long double x : sample_points<long double>())
assert(std::hermite(n, x) == std::hermitel(n, x));
}
{ // Checks if the characteristic recurrence relation holds: H_{n+1}(x) = 2x H_n(x) - 2n H_{n-1}(x)
for (Real x : sample_points<Real>()) {
- for (unsigned n = 1; n < g_max_n - 1; ++n) {
+ for (unsigned n = 1; n < get_maximal_order<Real>() - 1; ++n) {
Real H_next = std::hermite(n + 1, x);
Real H_next_recurrence = 2 * (x * std::hermite(n, x) - n * std::hermite(n - 1, x));
@@ -296,23 +300,23 @@ void test() {
}
}
-#if !(defined(__MVS__) && !defined(__BFP__))
- { // check input infinity is handled correctly
+ if constexpr (std::numeric_limits<Real>::has_infinity) { // check input infinity is handled correctly
Real inf = std::numeric_limits<Real>::infinity();
- for (unsigned n = 1; n < g_max_n; ++n) {
+ for (unsigned n = 1; n < get_maximal_order<Real>(); ++n) {
assert(std::hermite(n, +inf) == inf);
assert(std::hermite(n, -inf) == ((n & 1) ? -inf : inf));
}
}
- { // check: if overflow occurs that it is mapped to the correct infinity
+ if constexpr (std::numeric_limits<
+ Real>::has_infinity) { // check: if overflow occurs that it is mapped to the correct infinity
if constexpr (std::is_same_v<Real, double>) {
// Q: Why only double?
// A: The numeric values (e.g. overflow threshold `n`) below are different for other types.
static_assert(sizeof(double) == 8);
- for (unsigned n = 0; n < g_max_n; ++n) {
+ for (unsigned n = 0; n < get_maximal_order<Real>(); ++n) {
// Q: Why n=111 and x=300?
- // A: Both are chosen s.t. the first overlow occurs for some `n<g_max_n`.
+ // A: Both are chosen s.t. the first overlow occurs for some `n<get_maximal_order<Real>()`.
if (n < 111) {
assert(std::isfinite(std::hermite(n, +300.0)));
assert(std::isfinite(std::hermite(n, -300.0)));
@@ -324,7 +328,6 @@ void test() {
}
}
}
-#endif
}
struct TestFloat {
@@ -338,7 +341,7 @@ struct TestInt {
template <class Integer>
void operator()() {
// checks that std::hermite(unsigned, Integer) actually wraps std::hermite(unsigned, double)
- for (unsigned n = 0; n < g_max_n; ++n)
+ for (unsigned n = 0; n < get_maximal_order<double>(); ++n)
for (Integer x : {-42, -7, -5, -1, 0, 1, 5, 7, 42})
assert(std::hermite(n, x) == std::hermite(n, static_cast<double>(x)));
}
>From 112f3d98a0caa308cc5ad5551a33fae74cbca368 Mon Sep 17 00:00:00 2001
From: Zbigniew Sarbinowski <zibi at ca.ibm.com>
Date: Thu, 1 Aug 2024 18:36:45 +0000
Subject: [PATCH 4/5] Addressing comments ...
---
libcxx/test/std/numerics/c.math/hermite.pass.cpp | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/libcxx/test/std/numerics/c.math/hermite.pass.cpp b/libcxx/test/std/numerics/c.math/hermite.pass.cpp
index 28bf27cafc3dd..4b58d9170bdd8 100644
--- a/libcxx/test/std/numerics/c.math/hermite.pass.cpp
+++ b/libcxx/test/std/numerics/c.math/hermite.pass.cpp
@@ -28,10 +28,12 @@
template <class Real>
constexpr unsigned get_maximal_order() {
- if constexpr (std::numeric_limits<Real>::max_exponent10 < std::numeric_limits<Real>::max_exponent)
+ if constexpr (std::numeric_limits<Real>::max_exponent < 64)
+ return 39;
+ else if constexpr (std::numeric_limits<Real>::max_exponent < 129)
return 128;
else
- return 39;
+ return 1024;
}
template <class T>
>From 8dfb341ca0cbc684a54e6f34b29f9ac4de772b50 Mon Sep 17 00:00:00 2001
From: Zbigniew Sarbinowski <zibi at ca.ibm.com>
Date: Fri, 2 Aug 2024 20:42:23 +0000
Subject: [PATCH 5/5] more comments...
---
libcxx/test/std/numerics/c.math/hermite.pass.cpp | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/libcxx/test/std/numerics/c.math/hermite.pass.cpp b/libcxx/test/std/numerics/c.math/hermite.pass.cpp
index 4b58d9170bdd8..4283cbfd7bc18 100644
--- a/libcxx/test/std/numerics/c.math/hermite.pass.cpp
+++ b/libcxx/test/std/numerics/c.math/hermite.pass.cpp
@@ -28,12 +28,13 @@
template <class Real>
constexpr unsigned get_maximal_order() {
- if constexpr (std::numeric_limits<Real>::max_exponent < 64)
- return 39;
- else if constexpr (std::numeric_limits<Real>::max_exponent < 129)
+ if constexpr (std::numeric_limits<Real>::is_iec559)
return 128;
- else
- return 1024;
+ else { // Workaround for z/OS HexFloat.
+ // Note |H_n(x)| < 10^75 for n < 39 and x in sample_points().
+ static_assert(std::numeric_limits<Real>::max_exponent10 == 75);
+ return 39;
+ }
}
template <class T>
More information about the libcxx-commits
mailing list