On Mon May 27, 2024 at 9:12 AM AEST, BALATON Zoltan wrote:
> Invert conditions to avoid deep nested ifs and return early instead.
> Remove some obvious comments that don't add more clarity.
>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
> Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
> ---
> target/ppc/mmu_common.c | 43 ++++++++++++++++++-----------------------
> 1 file changed, 19 insertions(+), 24 deletions(-)
>
> diff --git a/target/ppc/mmu_common.c b/target/ppc/mmu_common.c
> index a5ae11394d..28adb3ca10 100644
> --- a/target/ppc/mmu_common.c
> +++ b/target/ppc/mmu_common.c
> @@ -99,31 +99,26 @@ static int ppc6xx_tlb_pte_check(mmu_ctx_t *ctx, target_ulong pte0,
> MMUAccessType access_type)
> {
> /* Check validity and table match */
> - if (pte_is_valid(pte0) && ((pte0 >> 6) & 1) == pteh) {
> - /* Check vsid & api */
> - if ((pte0 & PTE_PTEM_MASK) == ctx->ptem) {
> - if (ctx->raddr != (hwaddr)-1ULL) {
> - /* all matches should have equal RPN, WIMG & PP */
> - if ((ctx->raddr & PTE_CHECK_MASK) != (pte1 & PTE_CHECK_MASK)) {
> - qemu_log_mask(CPU_LOG_MMU, "Bad RPN/WIMG/PP\n");
> - return -3;
> - }
> - }
> - /* Keep the matching PTE information */
> - ctx->raddr = pte1;
> - ctx->prot = ppc_hash32_prot(ctx->key, pte1 & HPTE32_R_PP, ctx->nx);
> - if (check_prot_access_type(ctx->prot, access_type)) {
> - /* Access granted */
> - qemu_log_mask(CPU_LOG_MMU, "PTE access granted !\n");
> - return 0;
> - } else {
> - /* Access right violation */
> - qemu_log_mask(CPU_LOG_MMU, "PTE access rejected\n");
> - return -2;
> - }
> - }
> + if (!pte_is_valid(pte0) || ((pte0 >> 6) & 1) != pteh ||
> + (pte0 & PTE_PTEM_MASK) != ctx->ptem) {
> + return -1;
> + }
> + /* all matches should have equal RPN, WIMG & PP */
> + if (ctx->raddr != (hwaddr)-1ULL &&
> + (ctx->raddr & PTE_CHECK_MASK) != (pte1 & PTE_CHECK_MASK)) {
> + qemu_log_mask(CPU_LOG_MMU, "Bad RPN/WIMG/PP\n");
> + return -3;
> + }
> + /* Keep the matching PTE information */
> + ctx->raddr = pte1;
> + ctx->prot = ppc_hash32_prot(ctx->key, pte1 & HPTE32_R_PP, ctx->nx);
> + if (check_prot_access_type(ctx->prot, access_type)) {
> + qemu_log_mask(CPU_LOG_MMU, "PTE access granted !\n");
> + return 0;
> + } else {
> + qemu_log_mask(CPU_LOG_MMU, "PTE access rejected\n");
> + return -2;
> }
> - return -1;
> }
>
> static int pte_update_flags(mmu_ctx_t *ctx, target_ulong *pte1p,