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target/s390x: fake instruction loading when handling 'ex'

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The s390x EXecute instruction is a bit weird as we synthesis the
executed instruction from what we have stored in memory. This missed
the plugin instrumentation.

Work around this with a special helper to inform the rest of the
translator about the instruction so things stay consistent.

Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20221027183637.2772968-26-alex.bennee@linaro.org>
This commit is contained in:
Alex Bennée 2022-10-27 19:36:31 +01:00
parent 621aab6c7d
commit 9fa97e04ae
2 changed files with 23 additions and 0 deletions
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17
include/exec/translator.h
View File

@ -211,6 +211,23 @@ translator_ldq_swap(CPUArchState *env, DisasContextBase *db,
return ret;
}
/**
* translator_fake_ldb - fake instruction load
* @insn8: byte of instruction
* @pc: program counter of instruction
*
* This is a special case helper used where the instruction we are
* about to translate comes from somewhere else (e.g. being
* re-synthesised for s390x "ex"). It ensures we update other areas of
* the translator with details of the executed instruction.
*/
static inline void translator_fake_ldb(uint8_t insn8, abi_ptr pc)
{
plugin_insn_append(pc, &insn8, sizeof(insn8));
}
/*
* Return whether addr is on the same page as where disassembly started.
* Translators can use this to enforce the rule that only single-insn

6
target/s390x/tcg/translate.c
View File

@ -6317,12 +6317,18 @@ static const DisasInsn *extract_insn(CPUS390XState *env, DisasContext *s)
if (unlikely(s->ex_value)) {
/* Drop the EX data now, so that it's clear on exception paths. */
TCGv_i64 zero = tcg_const_i64(0);
int i;
tcg_gen_st_i64(zero, cpu_env, offsetof(CPUS390XState, ex_value));
tcg_temp_free_i64(zero);
/* Extract the values saved by EXECUTE. */
insn = s->ex_value & 0xffffffffffff0000ull;
ilen = s->ex_value & 0xf;
/* register insn bytes with translator so plugins work */
for (i = 0; i < ilen; i++) {
uint8_t byte = extract64(insn, 56 - (i * 8), 8);
translator_fake_ldb(byte, pc + i);
}
op = insn >> 56;
} else {
insn = ld_code2(env, s, pc);