diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 9f767127a7d..93e600d68f2 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,13 @@
+2019-08-12  Jakub Jelinek  <jakub@redhat.com>
+
+	PR target/83250
+	PR target/91340
+	* config/i386/avxintrin.h (_mm256_zextpd128_pd256,
+	_mm256_zextps128_ps256, _mm256_zextsi128_si256): New intrinsics.
+	* config/i386/avx512fintrin.h (_mm512_zextpd128_pd512,
+	_mm512_zextps128_ps512, _mm512_zextsi128_si512, _mm512_zextpd256_pd512,
+	_mm512_zextps256_ps512, _mm512_zextsi256_si512): Likewise.
+
 2019-08-12  Richard Biener  <rguenther@suse.de>
 
 	PR lto/91375
diff --git a/gcc/config/i386/avx512fintrin.h b/gcc/config/i386/avx512fintrin.h
index 454fd3d247d..c2ca4e15acd 100644
--- a/gcc/config/i386/avx512fintrin.h
+++ b/gcc/config/i386/avx512fintrin.h
@@ -15437,6 +15437,48 @@ _mm512_castsi256_si512 (__m256i __A)
   return (__m512i)__builtin_ia32_si512_256si ((__v8si)__A);
 }
 
+extern __inline __m512d
+__attribute__ ((__gnu_inline__, __always_inline__, __artificial__))
+_mm512_zextpd128_pd512 (__m128d __A)
+{
+  return (__m512d) _mm512_insertf32x4 (_mm512_setzero_ps (), (__m128) __A, 0);
+}
+
+extern __inline __m512
+__attribute__ ((__gnu_inline__, __always_inline__, __artificial__))
+_mm512_zextps128_ps512 (__m128 __A)
+{
+  return _mm512_insertf32x4 (_mm512_setzero_ps (), __A, 0);
+}
+
+extern __inline __m512i
+__attribute__ ((__gnu_inline__, __always_inline__, __artificial__))
+_mm512_zextsi128_si512 (__m128i __A)
+{
+  return _mm512_inserti32x4 (_mm512_setzero_si512 (), __A, 0);
+}
+
+extern __inline __m512d
+__attribute__ ((__gnu_inline__, __always_inline__, __artificial__))
+_mm512_zextpd256_pd512 (__m256d __A)
+{
+  return _mm512_insertf64x4 (_mm512_setzero_pd (), __A, 0);
+}
+
+extern __inline __m512
+__attribute__ ((__gnu_inline__, __always_inline__, __artificial__))
+_mm512_zextps256_ps512 (__m256 __A)
+{
+  return (__m512) _mm512_insertf64x4 (_mm512_setzero_pd (), (__m256d) __A, 0);
+}
+
+extern __inline __m512i
+__attribute__ ((__gnu_inline__, __always_inline__, __artificial__))
+_mm512_zextsi256_si512 (__m256i __A)
+{
+  return _mm512_inserti64x4 (_mm512_setzero_si512 (), __A, 0);
+}
+
 extern __inline __mmask16
 __attribute__ ((__gnu_inline__, __always_inline__, __artificial__))
 _mm512_cmpeq_epu32_mask (__m512i __A, __m512i __B)
diff --git a/gcc/config/i386/avxintrin.h b/gcc/config/i386/avxintrin.h
index 18c0711a8ad..c8f8d53c86f 100644
--- a/gcc/config/i386/avxintrin.h
+++ b/gcc/config/i386/avxintrin.h
@@ -1484,6 +1484,26 @@ _mm256_castsi128_si256 (__m128i __A)
   return (__m256i) __builtin_ia32_si256_si ((__v4si)__A);
 }
 
+/* Similarly, but with zero extension instead of undefined values.  */
+
+extern __inline __m256d __attribute__((__gnu_inline__, __always_inline__, __artificial__))
+_mm256_zextpd128_pd256 (__m128d __A)
+{
+  return _mm256_insertf128_pd (_mm256_setzero_pd (), __A, 0);
+}
+
+extern __inline __m256 __attribute__((__gnu_inline__, __always_inline__, __artificial__))
+_mm256_zextps128_ps256 (__m128 __A)
+{
+  return _mm256_insertf128_ps (_mm256_setzero_ps (), __A, 0);
+}
+
+extern __inline __m256i __attribute__((__gnu_inline__, __always_inline__, __artificial__))
+_mm256_zextsi128_si256 (__m128i __A)
+{
+  return _mm256_insertf128_si256 (_mm256_setzero_si256 (), __A, 0);
+}
+
 extern __inline __m256 __attribute__((__gnu_inline__, __always_inline__, __artificial__))
 _mm256_set_m128 ( __m128 __H, __m128 __L)
 {
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index d5267a84cfa..fc1175ff7bb 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,11 @@
+2019-08-12  Jakub Jelinek  <jakub@redhat.com>
+
+	PR target/83250
+	PR target/91340
+	* gcc.target/i386/avx-typecast-1.c: New test.
+	* gcc.target/i386/avx-typecast-2.c: New test.
+	* gcc.target/i386/avx512f-typecast-2.c: New test.
+
 2019-08-12  Ed Schonberg  <schonberg@adacore.com>
 
 	* gnat.dg/null_check.adb: New testcase.
diff --git a/gcc/testsuite/gcc.target/i386/avx-typecast-1.c b/gcc/testsuite/gcc.target/i386/avx-typecast-1.c
new file mode 100644
index 00000000000..3b5932644c5
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/avx-typecast-1.c
@@ -0,0 +1,83 @@
+/* { dg-do run } */
+/* { dg-options "-O2 -mavx" } */
+/* { dg-require-effective-target avx } */
+
+#include "avx-check.h"
+
+extern int memcmp (const void *, const void *, __SIZE_TYPE__);
+
+void
+avx_test (void)
+{
+  union256i_d  a, ad;
+  union256  b, bd;
+  union256d  c, cd;
+  union128i_d  d, dd;
+  union128  e, ed;
+  union128d  f, fd;
+  int i;
+
+  for (i = 0; i < 8; i++)
+    {
+      a.a[i] = 7146908634 + i;
+      b.a[i] = 45.12f + i;
+    }
+
+  for (i = 0; i < 4; i++)
+    {
+      c.a[i] = 41234512513451345.0905 + i;
+      d.a[i] = 109534 + i;
+      e.a[i] = 85034.095f + i;
+    }
+
+  for (i = 0; i < 2; i++)
+    f.a[i] = 41234512451345.0905 + i;
+
+  bd.x = _mm256_castpd_ps (c.x);
+  if (memcmp (bd.a, c.a, 32))
+    abort ();
+
+  ad.x = _mm256_castpd_si256 (c.x);
+  if (memcmp (ad.a, c.a, 32))
+    abort ();
+
+  cd.x = _mm256_castps_pd (b.x);
+  if (memcmp (cd.a, b.a, 32))
+    abort ();
+
+  ad.x = _mm256_castps_si256 (b.x);
+  if (memcmp (ad.a, b.a, 32))
+    abort ();
+
+  bd.x = _mm256_castsi256_ps (a.x);
+  if (memcmp (bd.a, a.a, 32))
+    abort ();
+
+  cd.x = _mm256_castsi256_pd (a.x);
+  if (memcmp (cd.a, a.a, 32))
+    abort ();
+
+  fd.x = _mm256_castpd256_pd128 (c.x);
+  if (memcmp (fd.a, c.a, 16))
+    abort ();
+
+  ed.x = _mm256_castps256_ps128 (b.x);
+  if (memcmp (ed.a, b.a, 16))
+    abort ();
+
+  dd.x = _mm256_castsi256_si128 (a.x);
+  if (memcmp (dd.a, a.a, 16))
+    abort ();
+
+  cd.x = _mm256_castpd128_pd256 (f.x);
+  if (memcmp (cd.a, f.a, 16))
+    abort ();
+
+  bd.x = _mm256_castps128_ps256 (e.x);
+  if (memcmp (bd.a, e.a, 16))
+    abort ();
+
+  ad.x = _mm256_castsi128_si256 (d.x);
+  if (memcmp (ad.a, d.a, 16))
+    abort ();
+}
diff --git a/gcc/testsuite/gcc.target/i386/avx-typecast-2.c b/gcc/testsuite/gcc.target/i386/avx-typecast-2.c
new file mode 100644
index 00000000000..679906781ae
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/avx-typecast-2.c
@@ -0,0 +1,46 @@
+/* { dg-do run } */
+/* { dg-options "-O2 -mavx" } */
+/* { dg-require-effective-target avx } */
+
+#include "avx-check.h"
+
+extern int memcmp (const void *, const void *, __SIZE_TYPE__);
+
+void
+avx_test (void)
+{
+  union256i_d ad, zero;
+  union256 bd;
+  union256d cd;
+  union128i_d d;
+  union128 e;
+  union128d f;
+  int i;
+
+  for (i = 0; i < 8; i++)
+    zero.a[i] = 0;
+
+  for (i = 0; i < 4; i++)
+    {
+      d.a[i] = 109534 + i;
+      e.a[i] = 85034.095f + i;
+    }
+
+  for (i = 0; i < 2; i++)
+    f.a[i] = 41234512451345.0905 + i;
+
+  cd.x = _mm256_zextpd128_pd256 (f.x);
+  if (memcmp (cd.a, f.a, 16)
+      || memcmp (&cd.a[2], &zero.a, 16))
+    abort ();
+
+  bd.x = _mm256_zextps128_ps256 (e.x);
+  if (memcmp (bd.a, e.a, 16)
+      || memcmp (&bd.a[4], &zero.a, 16))
+    abort ();
+
+  ad.x = _mm256_zextsi128_si256 (d.x);
+  if (memcmp (ad.a, d.a, 16)
+      || memcmp (&ad.a[4], &zero.a, 16))
+    abort ();
+}
diff --git a/gcc/testsuite/gcc.target/i386/avx512f-typecast-2.c b/gcc/testsuite/gcc.target/i386/avx512f-typecast-2.c
new file mode 100644
index 00000000000..a048342959c
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/avx512f-typecast-2.c
@@ -0,0 +1,71 @@
+/* { dg-do run } */
+/* { dg-options "-O2 -mavx512f" } */
+/* { dg-require-effective-target avx512f } */
+
+#include "avx512f-check.h"
+
+extern int memcmp (const void *, const void *, __SIZE_TYPE__);
+
+void
+avx512f_test (void)
+{
+  union512i_d ad, zero;
+  union512 bd;
+  union512d cd;
+  union256i_d d;
+  union256 e;
+  union256d f;
+  union128i_d g;
+  union128 h;
+  union128d k;
+  int i;
+
+  for (i = 0; i < 16; i++)
+    zero.a[i] = 0;
+
+  for (i = 0; i < 8; i++)
+    {
+      d.a[i] = 109534 + i;
+      e.a[i] = 85034.095f + i;
+    }
+
+  for (i = 0; i < 4; i++)
+    {
+      f.a[i] = 41234512451345.0905 + i;
+      g.a[i] = 71469086341 + i;
+      h.a[i] = 45.1264f + i;
+    }
+
+  for (i = 0; i < 2; i++)
+    k.a[i] = 7146908634.576 + i;
+
+  cd.x = _mm512_zextpd128_pd512 (k.x);
+  if (memcmp (cd.a, k.a, 16)
+      || memcmp (&cd.a[2], &zero.a, 48))
+    abort ();
+
+  bd.x = _mm512_zextps128_ps512 (h.x);
+  if (memcmp (bd.a, h.a, 16)
+      || memcmp (&bd.a[4], &zero.a, 48))
+    abort ();
+
+  ad.x = _mm512_zextsi128_si512 (g.x);
+  if (memcmp (ad.a, g.a, 16)
+      || memcmp (&ad.a[4], &zero.a, 48))
+    abort ();
+
+  cd.x = _mm512_zextpd256_pd512 (f.x);
+  if (memcmp (cd.a, f.a, 32)
+      || memcmp (&cd.a[4], &zero.a, 32))
+    abort ();
+
+  bd.x = _mm512_zextps256_ps512 (e.x);
+  if (memcmp (bd.a, e.a, 32)
+      || memcmp (&bd.a[8], &zero.a, 32))
+    abort ();
+
+  ad.x = _mm512_zextsi256_si512 (d.x);
+  if (memcmp (ad.a, d.a, 32)
+      || memcmp (&ad.a[8], &zero.a, 32))
+    abort ();
+}