Vector registers are zero initialized by the kernel. Stop accepting
"all ones" as a clean value.
Note that this was not working as expected given that
value == 0xff
can be assumed to be always false by the compiler as value's range is
[-128, 127]. Both GCC (-Wtype-limits) and clang
(-Wtautological-constant-out-of-range-compare) warn about this.
Reviewed-by: Charlie Jenkins <char...@rivosinc.com>
Tested-by: Charlie Jenkins <char...@rivosinc.com>
Signed-off-by: Ignacio Encinas <igna...@iencinas.com>
---
Changes in v2:
Remove code that becomes useless now that the only "clean" value for
vector registers is 0.
- Link to v1:
https://lore.kernel.org/r/20250305-fix-v_exec_initval_nolibc-v1-1-b87b60e43...@iencinas.com
---
tools/testing/selftests/riscv/vector/v_exec_initval_nolibc.c | 10 +++-------
1 file changed, 3 insertions(+), 7 deletions(-)
diff --git a/tools/testing/selftests/riscv/vector/v_exec_initval_nolibc.c
b/tools/testing/selftests/riscv/vector/v_exec_initval_nolibc.c
index
35c0812e32de0c82a54f84bd52c4272507121e35..4dde05e45a04122b566cedc36d20b072413b00e2
100644
--- a/tools/testing/selftests/riscv/vector/v_exec_initval_nolibc.c
+++ b/tools/testing/selftests/riscv/vector/v_exec_initval_nolibc.c
@@ -6,7 +6,7 @@
* the values. To further ensure consistency, this file is compiled without
* libc and without auto-vectorization.
*
- * To be "clean" all values must be either all ones or all zeroes.
+ * To be "clean" all values must be all zeroes.
*/
#define __stringify_1(x...) #x
@@ -14,9 +14,8 @@
int main(int argc, char **argv)
{
- char prev_value = 0, value;
+ char value = 0;
unsigned long vl;
- int first = 1;
if (argc > 2 && strcmp(argv[2], "x"))
asm volatile (
@@ -44,14 +43,11 @@ int main(int argc, char **argv)
"vsrl.vi " __stringify(register) ", "
__stringify(register) ", 8\n\t" \
".option pop\n\t"
\
: "=r" (value));
\
- if (first) {
\
- first = 0;
\
- } else if (value != prev_value || !(value == 0x00 || value ==
0xff)) { \
+ if (value != 0x00) {
\
printf("Register " __stringify(register)
\
" values not clean! value: %u\n", value);
\
exit(-1);
\
}
\
- prev_value = value;
\
}
\
})
---
base-commit: 03d38806a902b36bf364cae8de6f1183c0a35a67
change-id: 20250301-fix-v_exec_initval_nolibc-498d976c372d
Best regards,
--
Ignacio Encinas <igna...@iencinas.com>
