fp16-abi: add test to check that Float16 ABI matches with clang

fp16-abi/main.fmf

@@ -0,0 +1,32 @@
+summary: Test that Float16 ABI matches with clang
+test: "$WITH_SCL ./test.sh"
+framework: shell
+tier: 1
+component:
+  - llvm-toolset
+  - compiler-rt
+
+adjust:
+  - because: "Float16 not supported on s390x or ppc64le"
+    enabled: false
+    when: arch == s390x or arch == ppc64le
+
+  # Common requirements when LLVM is not SCL-ized
+  - require+:
+      - clang
+      - compiler-rt
+    when: collection is not defined
+
+  # Requirements for SCL-ized LLVM
+  - require+:
+      - llvm-toolset-13.0-clang
+      - llvm-toolset-13.0-compiler-rt
+    when: collection == llvm-toolset-13.0
+  - require+:
+      - llvm-toolset-14.0-clang
+      - llvm-toolset-14.0-compiler-rt
+    when: collection == llvm-toolset-14.0
+  - require+:
+      - llvm-toolset-15.0-clang
+      - llvm-toolset-15.0-compiler-rt
+    when: collection == llvm-toolset-15.0

fp16-abi/test.cpp

@@ -0,0 +1,14 @@
+// Reproducer based on this code from Steve Leung (evetsso):
+// https://github.com/ROCmSoftwarePlatform/rocFFT/issues/439#issuecomment-1693835987
+
+#include <iostream>
+#include <algorithm>
+#include <vector>
+
+int main()
+{
+    _Float16 one_f16 = 0.123;
+    float one_f32 = one_f16;
+    std::cout <<  one_f32 << std::endl;
+    return 0;
+}

fp16-abi/test.sh

@@ -0,0 +1,15 @@
+#!/bin/sh -ux
+# Do NOT set exit after error flag (set -e). Let all the optimizations to be run
+
+tmp=$(mktemp -d)
+result=0
+# Test the reproducer with all the optimization levels
+for opt_level in 0 1 2 3; do
+    clang++ --rtlib=compiler-rt -O$opt_level test.cpp -o $tmp/test_O$opt_level
+    $tmp/test_O$opt_level | grep '0.122986' || result=1
+done
+
+rm -rf $tmp
+if [[ "$result" == 1 ]]; then
+    exit 1
+fi