If the PC is in the last page of the address space, next_page_start
overflows to 0. Fix it.
Cc: Peter Maydell <peter.mayd...@linaro.org>
Signed-off-by: Emilio G. Cota <c...@braap.org>
---
target/arm/translate.h | 2 +-
target/arm/translate.c | 11 +++++------
2 files changed, 6 insertions(+), 7 deletions(-)
diff --git a/target/arm/translate.h b/target/arm/translate.h
index c47febf..2287894 100644
--- a/target/arm/translate.h
+++ b/target/arm/translate.h
@@ -9,7 +9,7 @@ typedef struct DisasContext {
DisasContextBase base;
target_ulong pc;
- target_ulong next_page_start;
+ target_ulong page_start;
uint32_t insn;
/* Nonzero if this instruction has been conditionally skipped. */
int condjmp;
diff --git a/target/arm/translate.c b/target/arm/translate.c
index fc03b5b..ade8d2d 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -9913,7 +9913,7 @@ static bool thumb_insn_is_16bit(DisasContext *s, uint32_t
insn)
return false;
}
- if ((insn >> 11) == 0x1e && (s->pc < s->next_page_start - 3)) {
+ if ((insn >> 11) == 0x1e && s->pc - s->page_start < TARGET_PAGE_SIZE - 3) {
/* 0b1111_0xxx_xxxx_xxxx : BL/BLX prefix, and the suffix
* is not on the next page; we merge this into a 32-bit
* insn.
@@ -12269,8 +12269,7 @@ static int arm_tr_init_disas_context(DisasContextBase
*dcbase,
dc->is_ldex = false;
dc->ss_same_el = false; /* Can't be true since EL_d must be AArch64 */
- dc->next_page_start =
- (dc->base.pc_first & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE;
+ dc->page_start = dc->base.pc_first & TARGET_PAGE_MASK;
/* If architectural single step active, limit to 1. */
if (is_singlestepping(dc)) {
@@ -12280,7 +12279,7 @@ static int arm_tr_init_disas_context(DisasContextBase
*dcbase,
/* ARM is a fixed-length ISA. Bound the number of insns to execute
to those left on the page. */
if (!dc->thumb) {
- int bound = (dc->next_page_start - dc->base.pc_first) / 4;
+ int bound = -(dc->base.pc_first | TARGET_PAGE_MASK) / 4;
max_insns = MIN(max_insns, bound);
}
@@ -12552,8 +12551,8 @@ static void thumb_tr_translate_insn(DisasContextBase
*dcbase, CPUState *cpu)
* but isn't very efficient).
*/
if (dc->base.is_jmp == DISAS_NEXT
- && (dc->pc >= dc->next_page_start
- || (dc->pc >= dc->next_page_start - 3
+ && (dc->pc - dc->page_start >= TARGET_PAGE_SIZE
+ || (dc->pc - dc->page_start >= TARGET_PAGE_SIZE - 3
&& insn_crosses_page(env, dc)))) {
dc->base.is_jmp = DISAS_TOO_MANY;
}
--
2.7.4
