[committed] libstdc++: Fix condition for supported SIMD types on ARMv8

[committed] libstdc++: Fix condition for supported SIMD types on ARMv8

[Matthias Kretz]

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pushed to trunk, will backport

tested on arm-linux-gnueabihf

---------- 8< ----------

Signed-off-by: Matthias Kretz <m.kretz@gsi.de>

libstdc++-v3/ChangeLog:

	PR libstdc++/110050
	* include/experimental/bits/simd.h (__vectorized_sizeof): With
	__have_neon_a32 only single-precision float works (in addition
	to integers).
---
 libstdc++-v3/include/experimental/bits/simd.h | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)


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──────────────────────────────────────────────────────────────────────────
 Dr. Matthias Kretz                           https://mattkretz.github.io
 GSI Helmholtz Centre for Heavy Ion Research               https://gsi.de
 stdₓ::simd
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diff --git a/libstdc++-v3/include/experimental/bits/simd.h b/libstdc++-v3/include/experimental/bits/simd.h
index f94b8361ab0..834fe923065 100644
--- a/libstdc++-v3/include/experimental/bits/simd.h
+++ b/libstdc++-v3/include/experimental/bits/simd.h
@@ -2808,8 +2808,10 @@ __vectorized_sizeof()
 	  return 16;
 
 	// ARM:
-	if constexpr (__have_neon_a64
-		      || (__have_neon_a32 && !is_same_v<_Tp, double>) )
+	if constexpr (__have_neon_a64)
+	  return 16;
+	if constexpr (__have_neon_a32 and (not is_floating_point_v<_Tp>
+					     or is_same_v<_Tp, float>))
 	  return 16;
 	if constexpr (__have_neon
 		      && sizeof(_Tp) < 8