On 8/26/22 13:23, Janis Schoetterl-Glausch wrote:
On Wed, 2022-08-24 at 11:35 +0200, Janosch Frank wrote:
On 7/20/22 16:25, Janis Schoetterl-Glausch wrote:
Generate specification exceptions and check that they occur.
Signed-off-by: Janis Schoetterl-Glausch <scgl@xxxxxxxxxxxxx>
---
s390x/Makefile | 1 +
lib/s390x/asm/arch_def.h | 5 ++
s390x/spec_ex.c | 180 +++++++++++++++++++++++++++++++++++++++
s390x/unittests.cfg | 3 +
4 files changed, 189 insertions(+)
create mode 100644 s390x/spec_ex.c
+
+/*
+ * Load possibly invalid psw, but setup fixup_psw before,
+ * so that fixup_invalid_psw() can bring us back onto the right track.
Not sure if the second line is needed as fixup_psw is a descriptive name
already.
+ * Also acts as compiler barrier, -> none required in expect/check_invalid_psw
+ */
+static void load_psw(struct psw psw)
+{
+ uint64_t scratch;
+
[...]
/*
Store a valid mask and the address of the nop into the fixup PSW.
Then load the possibly invalid PSW.
*/
This seems a bit redundant given the function comment, but I can
drop a comment in here describing how the fixup psw is computed.
Well, I skipped the function comment, got confused by the addr asm
variable and then decided to propose the comment.
It's a bit confusing since you have the invalid PSW and the global fixup
PSW in one function.
Maybe something like:
/* From here to the lpswe we're computing and setting the fixup PSW */
+ fixup_psw.mask = extract_psw_mask();
+ asm volatile ( "larl %[scratch],0f\n"
+ " stg %[scratch],%[addr]\n"
+ " lpswe %[psw]\n"
+ "0: nop\n"
+ : [scratch] "=&d"(scratch),
+ [addr] "=&T"(fixup_psw.addr)
s/addr/psw_addr/ ?
+ : [psw] "Q"(psw)
+ : "cc", "memory"
+ );
+}
+
+static void load_short_psw(struct short_psw psw)
+{
+ uint64_t scratch;
+
+ fixup_psw.mask = extract_psw_mask();
+ asm volatile ( "larl %[scratch],0f\n"
+ " stg %[scratch],%[addr]\n"
+ " lpsw %[psw]\n"
+ "0: nop\n"
+ : [scratch] "=&d"(scratch),
+ [addr] "=&T"(fixup_psw.addr)
+ : [psw] "Q"(psw)
+ : "cc", "memory"
+ );
Same story.
Do you want me to repeat the comments here or just rename addr?
Just rename addr
[...]
+static int not_even(void)
+{
+ uint64_t quad[2] __attribute__((aligned(16))) = {0};
+
+ asm volatile (".insn rxy,0xe3000000008f,%%r7,%[quad]" /* lpq %%r7,%[quad] */
+ : : [quad] "T"(quad)
Is there a reason you never put a space after the constraint?
TBH I never noticed I'm unusual in that regard. I guess I tend to think
of the operand and constraint as one entity.
I'll add the spaces.
+ : "%r7", "%r8"
+ );
+ return 0;
+}
+
[...]