[libcxx-commits] [libcxx] [libcxx][test][z/OS] Fix hermite.pass.cpp for HEX float (PR #101019)

[Zibi Sarbinowski via libcxx-commits]

https://github.com/zibi2 created https://github.com/llvm/llvm-project/pull/101019

The HEX float on z/OS does not have infinity nor NaN. In addition, the limits are smaller before the overflow occurs in mathematical calculations. This PR accounts for this.

FYI, this LIT test was recently added in PR [89982](https://github.com/llvm/llvm-project/pull/89982) 


>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] 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 {