mirrors/qemu
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

target/s390x: fix COMPARE LOGICAL LONG EXTENDED

Browse Source 
There are multiple issues with the COMPARE LOGICAL LONG EXTENDED
instruction:
- The test between the two operands is inverted, leading to an inversion
  of the cc values 1 and 2.
- The address and length of an operand continue to be decreased after
  reaching the end of this operand. These values are then wrong write
  back to the registers.
- We should limit the amount of bytes to process, so that interrupts can
  be served correctly.

At the same time rename dest into src1 and src into src3 to match the
operand names and make the code less confusing.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Message-Id: <20170531220129.27724-18-aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
This commit is contained in:
Aurelien Jarno 2017-06-01 00:01:16 +02:00 committed by Richard Henderson
parent 29a58fd85f
commit 84aa07f109
2 changed files with 52 additions and 22 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

54
target/s390x/mem_helper.c
View File

@ -666,35 +666,55 @@ uint32_t HELPER(clcle)(CPUS390XState *env, uint32_t r1, uint64_t a2,
uint32_t r3) uint32_t r3)
{ {
uintptr_t ra = GETPC(); uintptr_t ra = GETPC();
uint64_t destlen = get_length(env, r1 + 1); uint64_t src1len = get_length(env, r1 + 1);
uint64_t dest = get_address(env, r1); uint64_t src1 = get_address(env, r1);
uint64_t srclen = get_length(env, r3 + 1); uint64_t src3len = get_length(env, r3 + 1);
uint64_t src = get_address(env, r3); uint64_t src3 = get_address(env, r3);
uint8_t pad = a2 & 0xff; uint8_t pad = a2 & 0xff;
uint64_t len = MAX(src1len, src3len);
uint32_t cc = 0; uint32_t cc = 0;
if (!(destlen || srclen)) { if (!len) {
return cc; return cc;
} }
if (srclen > destlen) { /* Lest we fail to service interrupts in a timely manner, limit the
srclen = destlen; amount of work we're willing to do. For now, let's cap at 8k. */
if (len > 0x2000) {
len = 0x2000;
cc = 3;
} }
for (; destlen || srclen; src++, dest++, destlen--, srclen--) { for (; len; len--) {
uint8_t v1 = srclen ? cpu_ldub_data_ra(env, src, ra) : pad; uint8_t v1 = pad;
uint8_t v2 = destlen ? cpu_ldub_data_ra(env, dest, ra) : pad; uint8_t v3 = pad;
if (v1 != v2) {
cc = (v1 < v2) ? 1 : 2; if (src1len) {
v1 = cpu_ldub_data_ra(env, src1, ra);
}
if (src3len) {
v3 = cpu_ldub_data_ra(env, src3, ra);
}
if (v1 != v3) {
cc = (v1 < v3) ? 1 : 2;
break; break;
} }
if (src1len) {
src1++;
src1len--;
}
if (src3len) {
src3++;
src3len--;
}
} }
set_length(env, r1 + 1, destlen); set_length(env, r1 + 1, src1len);
/* can't use srclen here, we trunc'ed it */ set_length(env, r3 + 1, src3len);
set_length(env, r3 + 1, env->regs[r3 + 1] - src - env->regs[r3]); set_address(env, r1, src1);
set_address(env, r1, dest); set_address(env, r3, src3);
set_address(env, r3, src);
return cc; return cc;
} }

20
target/s390x/translate.c
View File

@ -1922,11 +1922,21 @@ static ExitStatus op_clc(DisasContext *s, DisasOps *o)
static ExitStatus op_clcle(DisasContext *s, DisasOps *o) static ExitStatus op_clcle(DisasContext *s, DisasOps *o)
{ {
TCGv_i32 r1 = tcg_const_i32(get_field(s->fields, r1)); int r1 = get_field(s->fields, r1);
TCGv_i32 r3 = tcg_const_i32(get_field(s->fields, r3)); int r3 = get_field(s->fields, r3);
gen_helper_clcle(cc_op, cpu_env, r1, o->in2, r3); TCGv_i32 t1, t3;
tcg_temp_free_i32(r1);
tcg_temp_free_i32(r3); /* r1 and r3 must be even. */
if (r1 & 1 || r3 & 1) {
gen_program_exception(s, PGM_SPECIFICATION);
return EXIT_NORETURN;
}
t1 = tcg_const_i32(r1);
t3 = tcg_const_i32(r3);
gen_helper_clcle(cc_op, cpu_env, t1, o->in2, t3);
tcg_temp_free_i32(t1);
tcg_temp_free_i32(t3);
set_cc_static(s); set_cc_static(s);
return NO_EXIT; return NO_EXIT;
} }