| Message ID | 20200324082235.27980-4-kuhn.chenqun@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | redundant code: Fix warnings reported by Clang static code analyzer | expand |
Le 24/03/2020 à 09:22, Chen Qun a écrit : > Clang static code analyzer show warning: > hw/timer/exynos4210_mct.c:1370:9: warning: Value stored to 'index' is never read > index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); > ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > hw/timer/exynos4210_mct.c:1399:9: warning: Value stored to 'index' is never read > index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); > ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > hw/timer/exynos4210_mct.c:1441:9: warning: Value stored to 'index' is never read > index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); > ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ It would be interesting to understand why we need the index for these registers in exynos4210_mct_read() and not in exynos4210_mct_write(). Thanks, Laurent > Reported-by: Euler Robot <euler.robot@huawei.com> > Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com> > --- > Cc: Igor Mitsyanko <i.mitsyanko@gmail.com> > Cc: Peter Maydell <peter.maydell@linaro.org> > --- > hw/timer/exynos4210_mct.c | 4 ---- > 1 file changed, 4 deletions(-) > > diff --git a/hw/timer/exynos4210_mct.c b/hw/timer/exynos4210_mct.c > index 944120aea5..570cf7075b 100644 > --- a/hw/timer/exynos4210_mct.c > +++ b/hw/timer/exynos4210_mct.c > @@ -1367,7 +1367,6 @@ static void exynos4210_mct_write(void *opaque, hwaddr offset, > > case L0_TCNTB: case L1_TCNTB: > lt_i = GET_L_TIMER_IDX(offset); > - index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); > > /* > * TCNTB is updated to internal register only after CNT expired. > @@ -1396,7 +1395,6 @@ static void exynos4210_mct_write(void *opaque, hwaddr offset, > > case L0_ICNTB: case L1_ICNTB: > lt_i = GET_L_TIMER_IDX(offset); > - index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); > > s->l_timer[lt_i].reg.wstat |= L_WSTAT_ICNTB_WRITE; > s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB] = value & > @@ -1438,8 +1436,6 @@ static void exynos4210_mct_write(void *opaque, hwaddr offset, > > case L0_FRCNTB: case L1_FRCNTB: > lt_i = GET_L_TIMER_IDX(offset); > - index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); > - > DPRINTF("local timer[%d] FRCNTB write %llx\n", lt_i, value); > > s->l_timer[lt_i].reg.wstat |= L_WSTAT_FRCCNTB_WRITE; >
>-----Original Message----- >From: Laurent Vivier [mailto:laurent@vivier.eu] >Sent: Tuesday, March 24, 2020 6:59 PM >To: Chenqun (kuhn) <kuhn.chenqun@huawei.com>; qemu-devel@nongnu.org; >qemu-trivial@nongnu.org >Cc: Zhanghailiang <zhang.zhanghailiang@huawei.com>; philmd@redhat.com; >Euler Robot <euler.robot@huawei.com>; Igor Mitsyanko ><i.mitsyanko@gmail.com>; Peter Maydell <peter.maydell@linaro.org> >Subject: Re: [PATCH v4 3/3] timer/exynos4210_mct: Remove redundant >statement in exynos4210_mct_write() > >Le 24/03/2020 à 09:22, Chen Qun a écrit : >> Clang static code analyzer show warning: >> hw/timer/exynos4210_mct.c:1370:9: warning: Value stored to 'index' is never >read >> index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); >> ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> hw/timer/exynos4210_mct.c:1399:9: warning: Value stored to 'index' is never >read >> index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); >> ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> hw/timer/exynos4210_mct.c:1441:9: warning: Value stored to 'index' is never >read >> index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); >> ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > >It would be interesting to understand why we need the index for these registers >in exynos4210_mct_read() and not in exynos4210_mct_write(). > I think the index can also be used in exynos4210_mct_write(), but the original author used a more obvious reg name instead of it. The obvious reg name: case L0_TCNTB: case L1_TCNTB: reg name is : L_REG_CNT_TCNTB case L0_ICNTB: case L1_ICNTB: reg name is : L_REG_CNT_ICNTB case L0_FRCNTB: case L1_FRCNTB: reg name is : L_REG_CNT_FRCCNTB Thanks. > >> Reported-by: Euler Robot <euler.robot@huawei.com> >> Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com> >> --- >> Cc: Igor Mitsyanko <i.mitsyanko@gmail.com> >> Cc: Peter Maydell <peter.maydell@linaro.org> >> --- >> hw/timer/exynos4210_mct.c | 4 ---- >> 1 file changed, 4 deletions(-) >> >> diff --git a/hw/timer/exynos4210_mct.c b/hw/timer/exynos4210_mct.c >> index 944120aea5..570cf7075b 100644 >> --- a/hw/timer/exynos4210_mct.c >> +++ b/hw/timer/exynos4210_mct.c >> @@ -1367,7 +1367,6 @@ static void exynos4210_mct_write(void *opaque, >> hwaddr offset, >> >> case L0_TCNTB: case L1_TCNTB: >> lt_i = GET_L_TIMER_IDX(offset); >> - index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); >> >> /* >> * TCNTB is updated to internal register only after CNT expired. >> @@ -1396,7 +1395,6 @@ static void exynos4210_mct_write(void *opaque, >> hwaddr offset, >> >> case L0_ICNTB: case L1_ICNTB: >> lt_i = GET_L_TIMER_IDX(offset); >> - index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); >> >> s->l_timer[lt_i].reg.wstat |= L_WSTAT_ICNTB_WRITE; >> s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB] = value & @@ >> -1438,8 +1436,6 @@ static void exynos4210_mct_write(void *opaque, >> hwaddr offset, >> >> case L0_FRCNTB: case L1_FRCNTB: >> lt_i = GET_L_TIMER_IDX(offset); >> - index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); >> - >> DPRINTF("local timer[%d] FRCNTB write %llx\n", lt_i, value); >> >> s->l_timer[lt_i].reg.wstat |= L_WSTAT_FRCCNTB_WRITE; >>
Le 24/03/2020 à 13:22, Chenqun (kuhn) a écrit : >> -----Original Message----- >> From: Laurent Vivier [mailto:laurent@vivier.eu] >> Sent: Tuesday, March 24, 2020 6:59 PM >> To: Chenqun (kuhn) <kuhn.chenqun@huawei.com>; qemu-devel@nongnu.org; >> qemu-trivial@nongnu.org >> Cc: Zhanghailiang <zhang.zhanghailiang@huawei.com>; philmd@redhat.com; >> Euler Robot <euler.robot@huawei.com>; Igor Mitsyanko >> <i.mitsyanko@gmail.com>; Peter Maydell <peter.maydell@linaro.org> >> Subject: Re: [PATCH v4 3/3] timer/exynos4210_mct: Remove redundant >> statement in exynos4210_mct_write() >> >> Le 24/03/2020 à 09:22, Chen Qun a écrit : >>> Clang static code analyzer show warning: >>> hw/timer/exynos4210_mct.c:1370:9: warning: Value stored to 'index' is never >> read >>> index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); >>> ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >>> hw/timer/exynos4210_mct.c:1399:9: warning: Value stored to 'index' is never >> read >>> index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); >>> ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >>> hw/timer/exynos4210_mct.c:1441:9: warning: Value stored to 'index' is never >> read >>> index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); >>> ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> >> It would be interesting to understand why we need the index for these registers >> in exynos4210_mct_read() and not in exynos4210_mct_write(). >> > I think the index can also be used in exynos4210_mct_write(), but the original author used a more obvious reg name instead of it. > > The obvious reg name: > case L0_TCNTB: case L1_TCNTB: > reg name is : L_REG_CNT_TCNTB > > case L0_ICNTB: case L1_ICNTB: > reg name is : L_REG_CNT_ICNTB > > case L0_FRCNTB: case L1_FRCNTB: > reg name is : L_REG_CNT_FRCCNTB > Yes, you're right. Computed index gives the value used with s->l_timer[lt_i].reg.cnt[]. Reviewed-by: Laurent Vivier <laurent@vivier.eu> Thanks, Laurent
diff --git a/hw/timer/exynos4210_mct.c b/hw/timer/exynos4210_mct.c index 944120aea5..570cf7075b 100644 --- a/hw/timer/exynos4210_mct.c +++ b/hw/timer/exynos4210_mct.c @@ -1367,7 +1367,6 @@ static void exynos4210_mct_write(void *opaque, hwaddr offset, case L0_TCNTB: case L1_TCNTB: lt_i = GET_L_TIMER_IDX(offset); - index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); /* * TCNTB is updated to internal register only after CNT expired. @@ -1396,7 +1395,6 @@ static void exynos4210_mct_write(void *opaque, hwaddr offset, case L0_ICNTB: case L1_ICNTB: lt_i = GET_L_TIMER_IDX(offset); - index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); s->l_timer[lt_i].reg.wstat |= L_WSTAT_ICNTB_WRITE; s->l_timer[lt_i].reg.cnt[L_REG_CNT_ICNTB] = value & @@ -1438,8 +1436,6 @@ static void exynos4210_mct_write(void *opaque, hwaddr offset, case L0_FRCNTB: case L1_FRCNTB: lt_i = GET_L_TIMER_IDX(offset); - index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); - DPRINTF("local timer[%d] FRCNTB write %llx\n", lt_i, value); s->l_timer[lt_i].reg.wstat |= L_WSTAT_FRCCNTB_WRITE;
Clang static code analyzer show warning: hw/timer/exynos4210_mct.c:1370:9: warning: Value stored to 'index' is never read index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ hw/timer/exynos4210_mct.c:1399:9: warning: Value stored to 'index' is never read index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ hw/timer/exynos4210_mct.c:1441:9: warning: Value stored to 'index' is never read index = GET_L_TIMER_CNT_REG_IDX(offset, lt_i); ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Reported-by: Euler Robot <euler.robot@huawei.com> Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com> --- Cc: Igor Mitsyanko <i.mitsyanko@gmail.com> Cc: Peter Maydell <peter.maydell@linaro.org> --- hw/timer/exynos4210_mct.c | 4 ---- 1 file changed, 4 deletions(-)