Hexagon: add PC alignment check and exception

The Hexagon Programmer's Reference Manual says that the exception 0x1e
should be raised upon an unaligned program counter. Let's implement that
and also add some tests.

Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Taylor Simpson <ltaylorsimpson@gmail.com>
Reviewed-by: Brian Cain <bcain@quicinc.com>
Message-Id: <277b7aeda2c717a96d4dde936b3ac77707cb6517.1714755107.git.quic_mathbern@quicinc.com>
Signed-off-by: Brian Cain <bcain@quicinc.com>
This commit is contained in:
Matheus Tavares Bernardino 2024-05-03 13:53:15 -03:00 committed by Brian Cain
parent a1852002c7
commit e1b526f1d8
7 changed files with 128 additions and 8 deletions

View file

@ -60,6 +60,10 @@ void cpu_loop(CPUHexagonState *env)
env->gpr[0] = ret;
}
break;
case HEX_EXCP_PC_NOT_ALIGNED:
force_sig_fault(TARGET_SIGBUS, TARGET_BUS_ADRALN,
env->gpr[HEX_REG_R31]);
break;
case EXCP_ATOMIC:
cpu_exec_step_atomic(cs);
break;

View file

@ -134,6 +134,10 @@ struct ArchCPU {
FIELD(TB_FLAGS, IS_TIGHT_LOOP, 0, 1)
G_NORETURN void hexagon_raise_exception_err(CPUHexagonState *env,
uint32_t exception,
uintptr_t pc);
static inline void cpu_get_tb_cpu_state(CPUHexagonState *env, vaddr *pc,
uint64_t *cs_base, uint32_t *flags)
{
@ -144,6 +148,9 @@ static inline void cpu_get_tb_cpu_state(CPUHexagonState *env, vaddr *pc,
hex_flags = FIELD_DP32(hex_flags, TB_FLAGS, IS_TIGHT_LOOP, 1);
}
*flags = hex_flags;
if (*pc & PCALIGN_MASK) {
hexagon_raise_exception_err(env, HEX_EXCP_PC_NOT_ALIGNED, 0);
}
}
typedef HexagonCPU ArchCPU;

View file

@ -20,9 +20,13 @@
#include "qemu/bitops.h"
#define PCALIGN 4
#define PCALIGN_MASK (PCALIGN - 1)
#define HEX_EXCP_FETCH_NO_UPAGE 0x012
#define HEX_EXCP_INVALID_PACKET 0x015
#define HEX_EXCP_INVALID_OPCODE 0x015
#define HEX_EXCP_PC_NOT_ALIGNED 0x01e
#define HEX_EXCP_PRIV_NO_UREAD 0x024
#define HEX_EXCP_PRIV_NO_UWRITE 0x025

View file

@ -22,9 +22,6 @@
#include "hex_regs.h"
#include "reg_fields.h"
#define PCALIGN 4
#define PCALIGN_MASK (PCALIGN - 1)
#define GET_FIELD(FIELD, REGIN) \
fEXTRACTU_BITS(REGIN, reg_field_info[FIELD].width, \
reg_field_info[FIELD].offset)

View file

@ -36,10 +36,9 @@
#define SF_MANTBITS 23
/* Exceptions processing helpers */
static G_NORETURN
void do_raise_exception_err(CPUHexagonState *env,
uint32_t exception,
uintptr_t pc)
G_NORETURN void hexagon_raise_exception_err(CPUHexagonState *env,
uint32_t exception,
uintptr_t pc)
{
CPUState *cs = env_cpu(env);
qemu_log_mask(CPU_LOG_INT, "%s: %d\n", __func__, exception);
@ -49,7 +48,7 @@ void do_raise_exception_err(CPUHexagonState *env,
G_NORETURN void HELPER(raise_exception)(CPUHexagonState *env, uint32_t excp)
{
do_raise_exception_err(env, excp, 0);
hexagon_raise_exception_err(env, excp, 0);
}
void log_store32(CPUHexagonState *env, target_ulong addr,

View file

@ -51,6 +51,7 @@ HEX_TESTS += scatter_gather
HEX_TESTS += hvx_misc
HEX_TESTS += hvx_histogram
HEX_TESTS += invalid-slots
HEX_TESTS += unaligned_pc
run-and-check-exception = $(call run-test,$2,$3 2>$2.stderr; \
test $$? -eq 1 && grep -q "exception $(strip $1)" $2.stderr)
@ -107,6 +108,7 @@ overflow: overflow.c hex_test.h
preg_alias: preg_alias.c hex_test.h
read_write_overlap: read_write_overlap.c hex_test.h
reg_mut: reg_mut.c hex_test.h
unaligned_pc: unaligned_pc.c
# This test has to be compiled for the -mv67t target
usr: usr.c hex_test.h

View file

@ -0,0 +1,107 @@
#include <stdio.h>
#include <signal.h>
#include <setjmp.h>
#include <stdlib.h>
/* will be changed in signal handler */
volatile sig_atomic_t completed_tests;
static jmp_buf after_test;
static int nr_tests;
void __attribute__((naked)) test_return(void)
{
asm volatile(
"allocframe(#0x8)\n"
"r0 = #0xffffffff\n"
"framekey = r0\n"
"dealloc_return\n"
:
:
: "r0", "r29", "r30", "r31", "framekey");
}
void test_endloop(void)
{
asm volatile(
"loop0(1f, #2)\n"
"1: r0 = #0x3\n"
"sa0 = r0\n"
"{ nop }:endloop0\n"
:
:
: "r0", "sa0", "lc0", "usr");
}
asm(
".pushsection .text.unaligned\n"
".org 0x3\n"
".global test_multi_cof_unaligned\n"
"test_multi_cof_unaligned:\n"
" jumpr r31\n"
".popsection\n"
);
#define SYS_EXIT 94
void test_multi_cof(void)
{
asm volatile(
"p0 = cmp.eq(r0, r0)\n"
"{\n"
" if (p0) jump test_multi_cof_unaligned\n"
" if (!p0) jump 1f\n"
"}\n"
"1:"
" r0 = #1\n"
" r6 = #%0\n"
" trap0(#1)\n"
:
: "i"(SYS_EXIT)
: "p0", "r0", "r6");
}
void sigbus_handler(int signum)
{
/* retore framekey after test_return */
asm volatile(
"r0 = #0\n"
"framekey = r0\n"
:
:
: "r0", "framekey");
printf("Test %d complete\n", completed_tests);
completed_tests++;
siglongjmp(after_test, 1);
}
void test_done(void)
{
int err = (completed_tests != nr_tests);
puts(err ? "FAIL" : "PASS");
exit(err);
}
typedef void (*test_fn)(void);
int main()
{
test_fn tests[] = { test_return, test_endloop, test_multi_cof, test_done };
nr_tests = (sizeof(tests) / sizeof(tests[0])) - 1;
struct sigaction sa = {
.sa_sigaction = sigbus_handler,
.sa_flags = SA_SIGINFO
};
if (sigaction(SIGBUS, &sa, NULL) < 0) {
perror("sigaction");
return EXIT_FAILURE;
}
sigsetjmp(after_test, 1);
tests[completed_tests]();
/* should never get here */
puts("FAIL");
return 1;
}