[C++] Make same_type_p return false for gnu_vector_type_p differences (PR 92789)

As Jason pointed out in the review of the C++ gnu_vector_type_p patch:

    https://gcc.gnu.org/ml/gcc-patches/2019-12/msg00173.html

the real fix for the XFAILs in acle/general-c++/gnu_vectors_*.C is to
make same_type_p return false for two types if one is gnu_vector_type_p
and the other isn't.  This patch does that and fixes the fallout.

Originally I'd tried to make it so that "X *" and "Y *" are
interconvertible whenever X and Y are, and similarly for
"X &" and "Y &".  That doesn't fall out naturally though,
and is different from how -flax-vector-conversions works.
The patch therefore accepts all the consequences of making
X and Y !same_type_p instead of trying to work around them.

2019-12-23  Richard Sandiford  <richard.sandiford@arm.com>

gcc/cp/
	PR c++/92789
	* typeck.c (structural_comptypes): Make sure that two vector types
	agree on gnu_vector_type_p.

gcc/testsuite/
	PR c++/92789
	* g++.dg/ext/sve-sizeless-2.C (statements): Expect pointer
	difference and comparisons between GNU and non-GNU types
	to be rejected.  Expect __is_same to be false for such pairs.
	* g++.target/aarch64/sve/acle/general-c++/gnu_vectors_1.C: Remove
	XFAILs.  Expect conversions between SVE vector pointers and
	GNU vector pointers to be rejected.  Test references.
	* g++.target/aarch64/sve/acle/general-c++/gnu_vectors_2.C: Likewise.

From-SVN: r279717

6 files changed, 83 insertions, 37 deletions

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 720c3ee..14c6d32 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,11 @@
 2019-12-23  Richard Sandiford  <richard.sandiford@arm.com>
 
+	PR c++/92789
+	* typeck.c (structural_comptypes): Make sure that two vector types
+	agree on gnu_vector_type_p.
+
+2019-12-23  Richard Sandiford  <richard.sandiford@arm.com>
+
 	* cvt.c (ocp_convert): Apply rvalue to the source of vector
 	conversions.
 	* typeck.c (build_reinterpret_cast_1): Likewise.
diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c
index d2f4a00..18c1685 100644
--- a/gcc/cp/typeck.c
+++ b/gcc/cp/typeck.c
@@ -1425,7 +1425,8 @@ structural_comptypes (tree t1, tree t2, int strict)
       break;
 
     case VECTOR_TYPE:
-      if (maybe_ne (TYPE_VECTOR_SUBPARTS (t1), TYPE_VECTOR_SUBPARTS (t2))
+      if (gnu_vector_type_p (t1) != gnu_vector_type_p (t2)
+	  || maybe_ne (TYPE_VECTOR_SUBPARTS (t1), TYPE_VECTOR_SUBPARTS (t2))
 	  || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
 	return false;
       break;
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 321d54b..59fc564 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,16 @@
 2019-12-23  Richard Sandiford  <richard.sandiford@arm.com>
 
+	PR c++/92789
+	* g++.dg/ext/sve-sizeless-2.C (statements): Expect pointer
+	difference and comparisons between GNU and non-GNU types
+	to be rejected.  Expect __is_same to be false for such pairs.
+	* g++.target/aarch64/sve/acle/general-c++/gnu_vectors_1.C: Remove
+	XFAILs.  Expect conversions between SVE vector pointers and
+	GNU vector pointers to be rejected.  Test references.
+	* g++.target/aarch64/sve/acle/general-c++/gnu_vectors_2.C: Likewise.
+
+2019-12-23  Richard Sandiford  <richard.sandiford@arm.com>
+
 	* g++.dg/ext/vector39.C: New test.
 
 2019-12-21  Andrew Pinski  <apinski@marvell.com>
diff --git a/gcc/testsuite/g++.dg/ext/sve-sizeless-2.C b/gcc/testsuite/g++.dg/ext/sve-sizeless-2.C
index f6b9c31..40b65d3 100644
--- a/gcc/testsuite/g++.dg/ext/sve-sizeless-2.C
+++ b/gcc/testsuite/g++.dg/ext/sve-sizeless-2.C
@@ -183,8 +183,8 @@ statements (int n)
 
   // Pointer assignment.
 
-  gnu_sc_ptr = sve_sc_ptr;
-  sve_sc_ptr = gnu_sc_ptr;
+  gnu_sc_ptr = sve_sc_ptr; // { dg-error {invalid conversion from 'svint8_t\*' to 'int8x32_t\*'} }
+  sve_sc_ptr = gnu_sc_ptr; // { dg-error {invalid conversion from 'int8x32_t\*'[^\n]* to 'svint8_t\*'} }
 
   // Pointer arithmetic.
 
@@ -197,8 +197,8 @@ statements (int n)
   sve_sc_ptr -= 0; // { dg-error {arithmetic on pointer to SVE type 'svint8_t'} }
   sve_sc_ptr -= 1; // { dg-error {arithmetic on pointer to SVE type 'svint8_t'} }
   sve_sc_ptr - sve_sc_ptr; // { dg-error {arithmetic on pointer to SVE type 'svint8_t'} }
-  gnu_sc_ptr - sve_sc_ptr; // { dg-error {arithmetic on pointer to SVE type 'svint8_t'} }
-  sve_sc_ptr - gnu_sc_ptr; // { dg-error {arithmetic on pointer to SVE type 'svint8_t'} }
+  gnu_sc_ptr - sve_sc_ptr; // { dg-error {invalid operands of types 'int8x32_t\*'[^\n]* and 'svint8_t\*' to binary 'operator-'} }
+  sve_sc_ptr - gnu_sc_ptr; // { dg-error {invalid operands of types 'svint8_t\*' and 'int8x32_t\*'[^\n]* to binary 'operator-'} }
   sve_sc1 = sve_sc_ptr[0]; // { dg-error {arithmetic on pointer to SVE type 'svint8_t'} }
   sve_sc1 = sve_sc_ptr[1]; // { dg-error {arithmetic on pointer to SVE type 'svint8_t'} }
 
@@ -210,18 +210,18 @@ statements (int n)
   sve_sc_ptr <= &sve_sc1;
   sve_sc_ptr > &sve_sc1;
   sve_sc_ptr >= &sve_sc1;
-  gnu_sc_ptr == sve_sc_ptr;
-  gnu_sc_ptr != sve_sc_ptr;
-  gnu_sc_ptr < sve_sc_ptr;
-  gnu_sc_ptr <= sve_sc_ptr;
-  gnu_sc_ptr > sve_sc_ptr;
-  gnu_sc_ptr >= sve_sc_ptr;
-  sve_sc_ptr == gnu_sc_ptr;
-  sve_sc_ptr != gnu_sc_ptr;
-  sve_sc_ptr < gnu_sc_ptr;
-  sve_sc_ptr <= gnu_sc_ptr;
-  sve_sc_ptr > gnu_sc_ptr;
-  sve_sc_ptr >= gnu_sc_ptr;
+  gnu_sc_ptr == sve_sc_ptr; // { dg-error {comparison between distinct pointer types [^\n]*lacks a cast} }
+  gnu_sc_ptr != sve_sc_ptr; // { dg-error {comparison between distinct pointer types [^\n]*lacks a cast} }
+  gnu_sc_ptr < sve_sc_ptr; // { dg-error {comparison between distinct pointer types [^\n]*lacks a cast} }
+  gnu_sc_ptr <= sve_sc_ptr; // { dg-error {comparison between distinct pointer types [^\n]*lacks a cast} }
+  gnu_sc_ptr > sve_sc_ptr; // { dg-error {comparison between distinct pointer types [^\n]*lacks a cast} }
+  gnu_sc_ptr >= sve_sc_ptr; // { dg-error {comparison between distinct pointer types [^\n]*lacks a cast} }
+  sve_sc_ptr == gnu_sc_ptr; // { dg-error {comparison between distinct pointer types [^\n]*lacks a cast} }
+  sve_sc_ptr != gnu_sc_ptr; // { dg-error {comparison between distinct pointer types [^\n]*lacks a cast} }
+  sve_sc_ptr < gnu_sc_ptr; // { dg-error {comparison between distinct pointer types [^\n]*lacks a cast} }
+  sve_sc_ptr <= gnu_sc_ptr; // { dg-error {comparison between distinct pointer types [^\n]*lacks a cast} }
+  sve_sc_ptr > gnu_sc_ptr; // { dg-error {comparison between distinct pointer types [^\n]*lacks a cast} }
+  sve_sc_ptr >= gnu_sc_ptr; // { dg-error {comparison between distinct pointer types [^\n]*lacks a cast} }
 
   // New and delete.
 
@@ -243,8 +243,8 @@ statements (int n)
   0 ? 0 : sve_sc1; // { dg-error {different types 'int' and 'svint8_t'} }
   0 ? sve_sc1 : sve_sc1;
   0 ? sve_sc_ptr : sve_sc_ptr;
-  0 ? sve_sc_ptr : gnu_sc_ptr;
-  0 ? gnu_sc_ptr : sve_sc_ptr;
+  0 ? sve_sc_ptr : gnu_sc_ptr; // { dg-error {conditional expression between distinct pointer types [^\n]*lacks a cast} }
+  0 ? gnu_sc_ptr : sve_sc_ptr; // { dg-error {conditional expression between distinct pointer types [^\n]*lacks a cast} }
 
   // Function arguments.
 
@@ -321,11 +321,11 @@ statements (int n)
   { typedef int f[__is_pod (svint8_t) ? 1 : -1]; }
   { typedef int f[!__is_polymorphic (svint8_t) ? 1 : -1]; }
   { typedef int f[__is_same_as (svint8_t, svint8_t) ? 1 : -1]; }
-  { typedef int f[__is_same_as (svint8_t, int8x32_t) ? 1 : -1]; }
-  { typedef int f[__is_same_as (int8x32_t, svint8_t) ? 1 : -1]; }
+  { typedef int f[!__is_same_as (svint8_t, int8x32_t) ? 1 : -1]; }
+  { typedef int f[!__is_same_as (int8x32_t, svint8_t) ? 1 : -1]; }
   { typedef int f[__is_same_as (svint8_t *, svint8_t *) ? 1 : -1]; }
-  { typedef int f[__is_same_as (svint8_t *, int8x32_t *) ? 1 : -1]; }
-  { typedef int f[__is_same_as (int8x32_t *, svint8_t *) ? 1 : -1]; }
+  { typedef int f[!__is_same_as (svint8_t *, int8x32_t *) ? 1 : -1]; }
+  { typedef int f[!__is_same_as (int8x32_t *, svint8_t *) ? 1 : -1]; }
   { typedef int f[!__is_same_as (svint8_t, int) ? 1 : -1]; }
   { typedef int f[!__is_same_as (svint8_t, svint16_t) ? 1 : -1]; }
   { typedef int f[__is_trivial (svint8_t) ? 1 : -1]; }
diff --git a/gcc/testsuite/g++.target/aarch64/sve/acle/general-c++/gnu_vectors_1.C b/gcc/testsuite/g++.target/aarch64/sve/acle/general-c++/gnu_vectors_1.C
index d1da64c..f60ffe4 100644
--- a/gcc/testsuite/g++.target/aarch64/sve/acle/general-c++/gnu_vectors_1.C
+++ b/gcc/testsuite/g++.target/aarch64/sve/acle/general-c++/gnu_vectors_1.C
@@ -36,14 +36,14 @@ f (svuint8_t sve_u1, svint8_t sve_s1,
 
   gnu_uint8_t init_gnu_u1 = 0; // { dg-error {cannot convert 'int' to 'gnu_uint8_t'[^\n]* in initialization} }
   gnu_uint8_t init_gnu_u2 = {};
-  gnu_uint8_t init_gnu_u3 = { sve_u1 };
+  gnu_uint8_t init_gnu_u3 = { sve_u1 }; // { dg-error {cannot convert 'svuint8_t' to 'unsigned char' in initialization} }
   gnu_uint8_t init_gnu_u4 = { gnu_u1 };
   gnu_uint8_t init_gnu_u5 = { sve_s1 }; // { dg-error {cannot convert 'svint8_t' to 'unsigned char' in initialization} }
   gnu_uint8_t init_gnu_u6 = { gnu_s1 }; // { dg-error {cannot convert 'gnu_int8_t'[^\n]* to 'unsigned char' in initialization} }
   gnu_uint8_t init_gnu_u7 = { 0 };
   gnu_uint8_t init_gnu_u8 = { sve_u1, sve_u1 }; // { dg-error {cannot convert 'svuint8_t' to 'unsigned char' in initialization} }
   gnu_uint8_t init_gnu_u9 = { gnu_u1, gnu_u1 }; // { dg-error {cannot convert 'gnu_uint8_t'[^\n]* to 'unsigned char' in initialization} }
-  gnu_uint8_t init_gnu_u10 { sve_u1 };
+  gnu_uint8_t init_gnu_u10 { sve_u1 }; // { dg-error {cannot convert 'svuint8_t' to 'unsigned char' in initialization} }
   gnu_uint8_t init_gnu_u11 { gnu_u1 };
   gnu_uint8_t init_gnu_u12 { sve_s1 }; // { dg-error {cannot convert 'svint8_t' to 'unsigned char' in initialization} }
   gnu_uint8_t init_gnu_u13 { gnu_s1 }; // { dg-error {cannot convert 'gnu_int8_t'[^\n]* to 'unsigned char' in initialization} }
@@ -69,7 +69,7 @@ f (svuint8_t sve_u1, svint8_t sve_s1,
 
   (gnu_uint8_t) {};
   (gnu_uint8_t) { 0 };
-  (gnu_uint8_t) { sve_u1 };
+  (gnu_uint8_t) { sve_u1 }; // { dg-error {cannot convert 'svuint8_t' to 'unsigned char' in initialization} }
   (gnu_uint8_t) { gnu_u1 };
   (gnu_uint8_t) { sve_s1 }; // { dg-error {cannot convert 'svint8_t' to 'unsigned char' in initialization} }
   (gnu_uint8_t) { gnu_s1 }; // { dg-error {cannot convert 'gnu_int8_t'[^\n]* to 'unsigned char' in initialization} }
@@ -434,8 +434,8 @@ f (svuint8_t sve_u1, svint8_t sve_s1,
   // Conditional expressions.
 
   uc ? sve_u1 : sve_u1;
-  uc ? gnu_u1 : sve_u1; // { dg-error {operands to '\?:' have different types 'gnu_uint8_t'[^\n]* and 'svuint8_t'} "" { xfail *-*-* } }
-  uc ? sve_u1 : gnu_u1; // { dg-error {operands to '\?:' have different types 'svuint8_t' and 'gnu_uint8_t'} "" { xfail *-*-* } }
+  uc ? gnu_u1 : sve_u1; // { dg-error {operands to '\?:' have different types 'gnu_uint8_t'[^\n]* and 'svuint8_t'} }
+  uc ? sve_u1 : gnu_u1; // { dg-error {operands to '\?:' have different types 'svuint8_t' and 'gnu_uint8_t'} }
   uc ? gnu_u1 : gnu_u1;
 
   sve_u1 ? sve_u1 : sve_u1; // { dg-error {could not convert 'sve_u1' from 'svuint8_t' to 'bool'} }
@@ -474,15 +474,29 @@ f (svuint8_t sve_u1, svint8_t sve_s1,
   static_assert(__is_literal_type(svuint8_t));
   static_assert(__is_literal_type(gnu_uint8_t));
 
+  // Pointers.
+
   svuint8_t *sve_ptr1 = &sve_u1;
-  svuint8_t *sve_ptr2 = &gnu_u1;
+  svuint8_t *sve_ptr2 = &gnu_u1; // { dg-error {invalid conversion} }
   svuint8_t *sve_ptr3 = &sve_s1; // { dg-error {cannot convert 'svint8_t\*' to 'svuint8_t\*' in initialization} }
   svuint8_t *sve_ptr4 = &gnu_s1; // { dg-error {cannot convert 'gnu_int8_t\*'[^\n]* to 'svuint8_t\*' in initialization} }
 
-  gnu_uint8_t *gnu_ptr1 = &sve_u1;
+  gnu_uint8_t *gnu_ptr1 = &sve_u1; // { dg-error {invalid conversion} }
   gnu_uint8_t *gnu_ptr2 = &gnu_u1;
   gnu_uint8_t *gnu_ptr3 = &sve_s1; // { dg-error {cannot convert 'svint8_t\*' to 'gnu_uint8_t\*'} }
   gnu_uint8_t *gnu_ptr4 = &gnu_s1; // { dg-error {cannot convert 'gnu_int8_t\*'[^\n]* to 'gnu_uint8_t\*'} }
+
+  // References.
+
+  svuint8_t &sve_ref1 = sve_u1;
+  svuint8_t &sve_ref2 = gnu_u1; // { dg-error {cannot bind non-const lvalue reference} }
+  svuint8_t &sve_ref3 = sve_s1; // { dg-error {invalid initialization of reference of type 'svuint8_t\&' from expression of type 'svint8_t'} }
+  svuint8_t &sve_ref4 = gnu_s1; // { dg-error {invalid initialization of reference of type 'svuint8_t\&' from expression of type 'gnu_int8_t'} }
+
+  gnu_uint8_t &gnu_ref1 = sve_u1; // { dg-error {cannot bind non-const lvalue reference} }
+  gnu_uint8_t &gnu_ref2 = gnu_u1;
+  gnu_uint8_t &gnu_ref3 = sve_s1; // { dg-error {invalid initialization of reference of type 'gnu_uint8_t\&} }
+  gnu_uint8_t &gnu_ref4 = gnu_s1; // { dg-error {invalid initialization of reference of type 'gnu_uint8_t\&} }
 }
 
 constexpr svuint8_t const1 (svuint8_t x) { return x; }
diff --git a/gcc/testsuite/g++.target/aarch64/sve/acle/general-c++/gnu_vectors_2.C b/gcc/testsuite/g++.target/aarch64/sve/acle/general-c++/gnu_vectors_2.C
index da4462b..30b2ca5 100644
--- a/gcc/testsuite/g++.target/aarch64/sve/acle/general-c++/gnu_vectors_2.C
+++ b/gcc/testsuite/g++.target/aarch64/sve/acle/general-c++/gnu_vectors_2.C
@@ -36,14 +36,14 @@ f (svuint8_t sve_u1, svint8_t sve_s1,
 
   gnu_uint8_t init_gnu_u1 = 0; // { dg-error {cannot convert 'int' to 'gnu_uint8_t'[^\n]* in initialization} }
   gnu_uint8_t init_gnu_u2 = {};
-  gnu_uint8_t init_gnu_u3 = { sve_u1 };
+  gnu_uint8_t init_gnu_u3 = { sve_u1 }; // { dg-error {cannot convert 'svuint8_t' to 'unsigned char' in initialization} }
   gnu_uint8_t init_gnu_u4 = { gnu_u1 };
   gnu_uint8_t init_gnu_u5 = { sve_s1 }; // { dg-error {cannot convert 'svint8_t' to 'unsigned char' in initialization} }
   gnu_uint8_t init_gnu_u6 = { gnu_s1 }; // { dg-error {cannot convert 'gnu_int8_t'[^\n]* to 'unsigned char' in initialization} }
   gnu_uint8_t init_gnu_u7 = { 0 };
   gnu_uint8_t init_gnu_u8 = { sve_u1, sve_u1 }; // { dg-error {cannot convert 'svuint8_t' to 'unsigned char' in initialization} }
   gnu_uint8_t init_gnu_u9 = { gnu_u1, gnu_u1 }; // { dg-error {cannot convert 'gnu_uint8_t'[^\n]* to 'unsigned char' in initialization} }
-  gnu_uint8_t init_gnu_u10 { sve_u1 };
+  gnu_uint8_t init_gnu_u10 { sve_u1 }; // { dg-error {cannot convert 'svuint8_t' to 'unsigned char' in initialization} }
   gnu_uint8_t init_gnu_u11 { gnu_u1 };
   gnu_uint8_t init_gnu_u12 { sve_s1 }; // { dg-error {cannot convert 'svint8_t' to 'unsigned char' in initialization} }
   gnu_uint8_t init_gnu_u13 { gnu_s1 }; // { dg-error {cannot convert 'gnu_int8_t'[^\n]* to 'unsigned char' in initialization} }
@@ -69,7 +69,7 @@ f (svuint8_t sve_u1, svint8_t sve_s1,
 
   (gnu_uint8_t) {};
   (gnu_uint8_t) { 0 };
-  (gnu_uint8_t) { sve_u1 };
+  (gnu_uint8_t) { sve_u1 }; // { dg-error {cannot convert 'svuint8_t' to 'unsigned char' in initialization} }
   (gnu_uint8_t) { gnu_u1 };
   (gnu_uint8_t) { sve_s1 }; // { dg-error {cannot convert 'svint8_t' to 'unsigned char' in initialization} }
   (gnu_uint8_t) { gnu_s1 }; // { dg-error {cannot convert 'gnu_int8_t'[^\n]* to 'unsigned char' in initialization} }
@@ -434,8 +434,8 @@ f (svuint8_t sve_u1, svint8_t sve_s1,
   // Conditional expressions.
 
   uc ? sve_u1 : sve_u1;
-  uc ? gnu_u1 : sve_u1; // { dg-error {operands to '\?:' have different types 'gnu_uint8_t'[^\n]* and 'svuint8_t'} "" { xfail *-*-* } }
-  uc ? sve_u1 : gnu_u1; // { dg-error {operands to '\?:' have different types 'svuint8_t' and 'gnu_uint8_t'} "" { xfail *-*-* } }
+  uc ? gnu_u1 : sve_u1; // { dg-error {operands to '\?:' have different types 'gnu_uint8_t'[^\n]* and 'svuint8_t'} }
+  uc ? sve_u1 : gnu_u1; // { dg-error {operands to '\?:' have different types 'svuint8_t' and 'gnu_uint8_t'} }
   uc ? gnu_u1 : gnu_u1;
 
   sve_u1 ? sve_u1 : sve_u1; // { dg-error {could not convert 'sve_u1' from 'svuint8_t' to 'bool'} }
@@ -474,15 +474,29 @@ f (svuint8_t sve_u1, svint8_t sve_s1,
   static_assert(__is_literal_type(svuint8_t));
   static_assert(__is_literal_type(gnu_uint8_t));
 
+  // Pointers.
+
   svuint8_t *sve_ptr1 = &sve_u1;
-  svuint8_t *sve_ptr2 = &gnu_u1;
+  svuint8_t *sve_ptr2 = &gnu_u1; // { dg-error {invalid conversion} }
   svuint8_t *sve_ptr3 = &sve_s1; // { dg-error {invalid conversion from 'svint8_t\*' to 'svuint8_t\*'} }
   svuint8_t *sve_ptr4 = &gnu_s1; // { dg-error {invalid conversion from 'gnu_int8_t\*'[^\n]* to 'svuint8_t\*'} }
 
-  gnu_uint8_t *gnu_ptr1 = &sve_u1;
+  gnu_uint8_t *gnu_ptr1 = &sve_u1; // { dg-error {invalid conversion} }
   gnu_uint8_t *gnu_ptr2 = &gnu_u1;
   gnu_uint8_t *gnu_ptr3 = &sve_s1; // { dg-error {invalid conversion from 'svint8_t\*' to 'gnu_uint8_t\*'} }
   gnu_uint8_t *gnu_ptr4 = &gnu_s1; // { dg-error {invalid conversion from 'gnu_int8_t\*'[^\n]* to 'gnu_uint8_t\*'} }
+
+  // References.
+
+  svuint8_t &sve_ref1 = sve_u1;
+  svuint8_t &sve_ref2 = gnu_u1; // { dg-error {cannot bind non-const lvalue reference} }
+  svuint8_t &sve_ref3 = sve_s1; // { dg-error {cannot bind non-const lvalue reference} }
+  svuint8_t &sve_ref4 = gnu_s1; // { dg-error {cannot bind non-const lvalue reference} }
+
+  gnu_uint8_t &gnu_ref1 = sve_u1; // { dg-error {cannot bind non-const lvalue reference} }
+  gnu_uint8_t &gnu_ref2 = gnu_u1;
+  gnu_uint8_t &gnu_ref3 = sve_s1; // { dg-error {cannot bind non-const lvalue reference} }
+  gnu_uint8_t &gnu_ref4 = gnu_s1; // { dg-error {cannot bind non-const lvalue reference} }
 }
 
 constexpr svuint8_t const1 (svuint8_t x) { return x; }