libstdc++: Skip integer division optimization for Clang

Clang ICEs on _SimdImplX86::_S_divides. The function is only working
around a missed optimization and not necessary for correctness.
Therefore, don't use it for Clang.

Signed-off-by: Matthias Kretz <m.kretz@gsi.de>
libstdc++-v3/ChangeLog:

	* include/experimental/bits/simd_detail.h: Don't define
	_GLIBCXX_SIMD_WORKAROUND_PR90993 for Clang.
	* include/experimental/bits/simd_x86.h (_S_divides): Remove
	check for __clang__.

(cherry picked from commit 403e48ef441b0502af46ad3598f699f4a1611791)

diff --git a/libstdc++-v3/include/experimental/bits/simd_detail.h b/libstdc++-v3/include/experimental/bits/simd_detail.h
index 9135d3e75d346f3365e45218e59c4f1a228eff16..de8d018c515ee71951b40576959e75606ee457bf 100644 (file)
--- a/libstdc++-v3/include/experimental/bits/simd_detail.h
+++ b/libstdc++-v3/include/experimental/bits/simd_detail.h
@@ -316,7 +316,9 @@
 #endif
 
 // integer division not optimized
+#ifndef __clang__
 #define _GLIBCXX_SIMD_WORKAROUND_PR90993 1
+#endif
 
 // very bad codegen for extraction and concatenation of 128/256 "subregisters"
 // with sizeof(element type) < 8: https://godbolt.org/g/mqUsgM

diff --git a/libstdc++-v3/include/experimental/bits/simd_x86.h b/libstdc++-v3/include/experimental/bits/simd_x86.h
index b9af1ce538cf80a957dda00129c94077146737d6..53e886c51364c33acb2e7f96f4609740a518a13f 100644 (file)
--- a/libstdc++-v3/include/experimental/bits/simd_x86.h
+++ b/libstdc++-v3/include/experimental/bits/simd_x86.h
@@ -1422,7 +1422,7 @@ template <typename _Abi, typename>
                },
                [&__xf,
                 &__yf](auto __i) -> _SimdWrapper<_Float, __n_intermediate> {
-#if !defined __clang__ && __GCC_IEC_559 == 0
+#if __GCC_IEC_559 == 0
                  // If -freciprocal-math is active, using the `/` operator is
                  // incorrect because it may be translated to an imprecise
                  // multiplication with reciprocal. We need to use inline
@@ -1477,7 +1477,7 @@ template <typename _Abi, typename>
          */
        return _Base::_S_divides(__x, __y);
       }
-  #endif // _GLIBCXX_SIMD_WORKAROUND_PR90993
+#endif // _GLIBCXX_SIMD_WORKAROUND_PR90993
 
     // }}}
     // _S_modulus {{{