* [Qemu-devel] [PATCH v2 4/9] Convert (ffs(val) - 1) to ctz32(val)
2015-03-17 15:09 [Qemu-devel] [PATCH v2 0/9] Convert ffs(3) to ctz32() Stefan Hajnoczi
` (2 preceding siblings ...)
2015-03-17 15:09 ` [Qemu-devel] [PATCH v2 3/9] uninorth: " Stefan Hajnoczi
@ 2015-03-17 15:09 ` Stefan Hajnoczi
2015-03-17 15:09 ` [Qemu-devel] [PATCH v2 5/9] Convert ffs() != 0 callers to ctz32() Stefan Hajnoczi
` (4 subsequent siblings)
8 siblings, 0 replies; 10+ messages in thread
From: Stefan Hajnoczi @ 2015-03-17 15:09 UTC (permalink / raw)
To: qemu-devel; +Cc: Peter Maydell, Markus Armbruster, Stefan Hajnoczi
This commit was generated mechanically by coccinelle from the following
semantic patch:
@@
expression val;
@@
- (ffs(val) - 1)
+ ctz32(val)
The call sites have been audited to ensure the ffs(0) - 1 == -1 case
never occurs (due to input validation, asserts, etc). Therefore we
don't need to worry about the fact that ctz32(0) == 32.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
block.c | 2 +-
block/qcow2-refcount.c | 2 +-
block/qcow2.c | 4 ++--
block/qed.c | 4 ++--
block/rbd.c | 2 +-
block/sheepdog.c | 2 +-
hw/acpi/pcihp.c | 2 +-
hw/arm/pxa2xx_gpio.c | 2 +-
hw/arm/strongarm.c | 4 ++--
hw/display/tc6393xb.c | 2 +-
hw/gpio/max7310.c | 2 +-
hw/gpio/zaurus.c | 2 +-
hw/pci-host/bonito.c | 2 +-
hw/pci/msi.c | 12 ++++++------
hw/pci/pcie_aer.c | 2 +-
hw/pci/shpc.c | 10 +++++-----
hw/pci/slotid_cap.c | 2 +-
hw/ppc/ppce500_spin.c | 2 +-
hw/scsi/megasas.c | 2 +-
include/hw/pci/pci.h | 16 ++++++++--------
include/hw/pci/pcie_regs.h | 18 +++++++++---------
target-ppc/cpu.h | 4 ++--
22 files changed, 50 insertions(+), 50 deletions(-)
diff --git a/block.c b/block.c
index 191a847..2eab818 100644
--- a/block.c
+++ b/block.c
@@ -5421,7 +5421,7 @@ BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs, int granularity,
return NULL;
}
bitmap = g_new0(BdrvDirtyBitmap, 1);
- bitmap->bitmap = hbitmap_alloc(bitmap_size, ffs(granularity) - 1);
+ bitmap->bitmap = hbitmap_alloc(bitmap_size, ctz32(granularity));
QLIST_INSERT_HEAD(&bs->dirty_bitmaps, bitmap, list);
return bitmap;
}
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
index dc8d186..8804419 100644
--- a/block/qcow2-refcount.c
+++ b/block/qcow2-refcount.c
@@ -2438,7 +2438,7 @@ int qcow2_pre_write_overlap_check(BlockDriverState *bs, int ign, int64_t offset,
if (ret < 0) {
return ret;
} else if (ret > 0) {
- int metadata_ol_bitnr = ffs(ret) - 1;
+ int metadata_ol_bitnr = ctz32(ret);
assert(metadata_ol_bitnr < QCOW2_OL_MAX_BITNR);
qcow2_signal_corruption(bs, true, offset, size, "Preventing invalid "
diff --git a/block/qcow2.c b/block/qcow2.c
index 32bdf75..5abca2e 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -1788,7 +1788,7 @@ static int qcow2_create2(const char *filename, int64_t total_size,
{
/* Calculate cluster_bits */
int cluster_bits;
- cluster_bits = ffs(cluster_size) - 1;
+ cluster_bits = ctz32(cluster_size);
if (cluster_bits < MIN_CLUSTER_BITS || cluster_bits > MAX_CLUSTER_BITS ||
(1 << cluster_bits) != cluster_size)
{
@@ -2096,7 +2096,7 @@ static int qcow2_create(const char *filename, QemuOpts *opts, Error **errp)
goto finish;
}
- refcount_order = ffs(refcount_bits) - 1;
+ refcount_order = ctz32(refcount_bits);
ret = qcow2_create2(filename, size, backing_file, backing_fmt, flags,
cluster_size, prealloc, opts, version, refcount_order,
diff --git a/block/qed.c b/block/qed.c
index 892b13c..9d90888 100644
--- a/block/qed.c
+++ b/block/qed.c
@@ -436,9 +436,9 @@ static int bdrv_qed_open(BlockDriverState *bs, QDict *options, int flags,
s->table_nelems = (s->header.cluster_size * s->header.table_size) /
sizeof(uint64_t);
- s->l2_shift = ffs(s->header.cluster_size) - 1;
+ s->l2_shift = ctz32(s->header.cluster_size);
s->l2_mask = s->table_nelems - 1;
- s->l1_shift = s->l2_shift + ffs(s->table_nelems) - 1;
+ s->l1_shift = s->l2_shift + ctz32(s->table_nelems);
/* Header size calculation must not overflow uint32_t */
if (s->header.header_size > UINT32_MAX / s->header.cluster_size) {
diff --git a/block/rbd.c b/block/rbd.c
index f3ab2dd..fbe87e0 100644
--- a/block/rbd.c
+++ b/block/rbd.c
@@ -325,7 +325,7 @@ static int qemu_rbd_create(const char *filename, QemuOpts *opts, Error **errp)
error_setg(errp, "obj size too small");
return -EINVAL;
}
- obj_order = ffs(objsize) - 1;
+ obj_order = ctz32(objsize);
}
clientname = qemu_rbd_parse_clientname(conf, clientname_buf);
diff --git a/block/sheepdog.c b/block/sheepdog.c
index c14172c..2d5f06a 100644
--- a/block/sheepdog.c
+++ b/block/sheepdog.c
@@ -1716,7 +1716,7 @@ static int parse_block_size_shift(BDRVSheepdogState *s, QemuOpts *opt)
if ((object_size - 1) & object_size) { /* not a power of 2? */
return -EINVAL;
}
- obj_order = ffs(object_size) - 1;
+ obj_order = ctz32(object_size);
if (obj_order < 20 || obj_order > 31) {
return -EINVAL;
}
diff --git a/hw/acpi/pcihp.c b/hw/acpi/pcihp.c
index 612fec0..77e1126 100644
--- a/hw/acpi/pcihp.c
+++ b/hw/acpi/pcihp.c
@@ -120,7 +120,7 @@ static bool acpi_pcihp_pc_no_hotplug(AcpiPciHpState *s, PCIDevice *dev)
static void acpi_pcihp_eject_slot(AcpiPciHpState *s, unsigned bsel, unsigned slots)
{
BusChild *kid, *next;
- int slot = ffs(slots) - 1;
+ int slot = ctz32(slots);
PCIBus *bus = acpi_pcihp_find_hotplug_bus(s, bsel);
if (!bus) {
diff --git a/hw/arm/pxa2xx_gpio.c b/hw/arm/pxa2xx_gpio.c
index 354ccf1..c89c804 100644
--- a/hw/arm/pxa2xx_gpio.c
+++ b/hw/arm/pxa2xx_gpio.c
@@ -137,7 +137,7 @@ static void pxa2xx_gpio_handler_update(PXA2xxGPIOInfo *s) {
level = s->olevel[i] & s->dir[i];
for (diff = s->prev_level[i] ^ level; diff; diff ^= 1 << bit) {
- bit = ffs(diff) - 1;
+ bit = ctz32(diff);
line = bit + 32 * i;
qemu_set_irq(s->handler[line], (level >> bit) & 1);
}
diff --git a/hw/arm/strongarm.c b/hw/arm/strongarm.c
index 3206345..035d328 100644
--- a/hw/arm/strongarm.c
+++ b/hw/arm/strongarm.c
@@ -526,7 +526,7 @@ static void strongarm_gpio_handler_update(StrongARMGPIOInfo *s)
level = s->olevel & s->dir;
for (diff = s->prev_level ^ level; diff; diff ^= 1 << bit) {
- bit = ffs(diff) - 1;
+ bit = ctz32(diff);
qemu_set_irq(s->handler[bit], (level >> bit) & 1);
}
@@ -743,7 +743,7 @@ static void strongarm_ppc_handler_update(StrongARMPPCInfo *s)
level = s->olevel & s->dir;
for (diff = s->prev_level ^ level; diff; diff ^= 1 << bit) {
- bit = ffs(diff) - 1;
+ bit = ctz32(diff);
qemu_set_irq(s->handler[bit], (level >> bit) & 1);
}
diff --git a/hw/display/tc6393xb.c b/hw/display/tc6393xb.c
index 4306adc..66b7ade 100644
--- a/hw/display/tc6393xb.c
+++ b/hw/display/tc6393xb.c
@@ -171,7 +171,7 @@ static void tc6393xb_gpio_handler_update(TC6393xbState *s)
level = s->gpio_level & s->gpio_dir;
for (diff = s->prev_level ^ level; diff; diff ^= 1 << bit) {
- bit = ffs(diff) - 1;
+ bit = ctz32(diff);
qemu_set_irq(s->handler[bit], (level >> bit) & 1);
}
diff --git a/hw/gpio/max7310.c b/hw/gpio/max7310.c
index 7fbf313..2f59b13 100644
--- a/hw/gpio/max7310.c
+++ b/hw/gpio/max7310.c
@@ -96,7 +96,7 @@ static int max7310_tx(I2CSlave *i2c, uint8_t data)
case 0x01: /* Output port */
for (diff = (data ^ s->level) & ~s->direction; diff;
diff &= ~(1 << line)) {
- line = ffs(diff) - 1;
+ line = ctz32(diff);
if (s->handler[line])
qemu_set_irq(s->handler[line], (data >> line) & 1);
}
diff --git a/hw/gpio/zaurus.c b/hw/gpio/zaurus.c
index 9408342..24a7727 100644
--- a/hw/gpio/zaurus.c
+++ b/hw/gpio/zaurus.c
@@ -65,7 +65,7 @@ static inline void scoop_gpio_handler_update(ScoopInfo *s) {
level = s->gpio_level & s->gpio_dir;
for (diff = s->prev_level ^ level; diff; diff ^= 1 << bit) {
- bit = ffs(diff) - 1;
+ bit = ctz32(diff);
qemu_set_irq(s->handler[bit], (level >> bit) & 1);
}
diff --git a/hw/pci-host/bonito.c b/hw/pci-host/bonito.c
index 8bdd569..1fe43e0 100644
--- a/hw/pci-host/bonito.c
+++ b/hw/pci-host/bonito.c
@@ -427,7 +427,7 @@ static uint32_t bonito_sbridge_pciaddr(void *opaque, hwaddr addr)
cfgaddr |= (s->regs[BONITO_PCIMAP_CFG] & 0xffff) << 16;
idsel = (cfgaddr & BONITO_PCICONF_IDSEL_MASK) >> BONITO_PCICONF_IDSEL_OFFSET;
- devno = ffs(idsel) - 1;
+ devno = ctz32(idsel);
funno = (cfgaddr & BONITO_PCICONF_FUN_MASK) >> BONITO_PCICONF_FUN_OFFSET;
regno = (cfgaddr & BONITO_PCICONF_REG_MASK) >> BONITO_PCICONF_REG_OFFSET;
diff --git a/hw/pci/msi.c b/hw/pci/msi.c
index 52d2313..9fadbc6 100644
--- a/hw/pci/msi.c
+++ b/hw/pci/msi.c
@@ -72,7 +72,7 @@ static inline uint8_t msi_cap_sizeof(uint16_t flags)
static inline unsigned int msi_nr_vectors(uint16_t flags)
{
return 1U <<
- ((flags & PCI_MSI_FLAGS_QSIZE) >> (ffs(PCI_MSI_FLAGS_QSIZE) - 1));
+ ((flags & PCI_MSI_FLAGS_QSIZE) >> ctz32(PCI_MSI_FLAGS_QSIZE));
}
static inline uint8_t msi_flags_off(const PCIDevice* dev)
@@ -175,9 +175,9 @@ int msi_init(struct PCIDevice *dev, uint8_t offset,
assert(nr_vectors > 0);
assert(nr_vectors <= PCI_MSI_VECTORS_MAX);
/* the nr of MSI vectors is up to 32 */
- vectors_order = ffs(nr_vectors) - 1;
+ vectors_order = ctz32(nr_vectors);
- flags = vectors_order << (ffs(PCI_MSI_FLAGS_QMASK) - 1);
+ flags = vectors_order << ctz32(PCI_MSI_FLAGS_QMASK);
if (msi64bit) {
flags |= PCI_MSI_FLAGS_64BIT;
}
@@ -354,12 +354,12 @@ void msi_write_config(PCIDevice *dev, uint32_t addr, uint32_t val, int len)
* just don't crash the host
*/
log_num_vecs =
- (flags & PCI_MSI_FLAGS_QSIZE) >> (ffs(PCI_MSI_FLAGS_QSIZE) - 1);
+ (flags & PCI_MSI_FLAGS_QSIZE) >> ctz32(PCI_MSI_FLAGS_QSIZE);
log_max_vecs =
- (flags & PCI_MSI_FLAGS_QMASK) >> (ffs(PCI_MSI_FLAGS_QMASK) - 1);
+ (flags & PCI_MSI_FLAGS_QMASK) >> ctz32(PCI_MSI_FLAGS_QMASK);
if (log_num_vecs > log_max_vecs) {
flags &= ~PCI_MSI_FLAGS_QSIZE;
- flags |= log_max_vecs << (ffs(PCI_MSI_FLAGS_QSIZE) - 1);
+ flags |= log_max_vecs << ctz32(PCI_MSI_FLAGS_QSIZE);
pci_set_word(dev->config + msi_flags_off(dev), flags);
}
diff --git a/hw/pci/pcie_aer.c b/hw/pci/pcie_aer.c
index 5a25c32..aeba034 100644
--- a/hw/pci/pcie_aer.c
+++ b/hw/pci/pcie_aer.c
@@ -410,7 +410,7 @@ static void pcie_aer_msg(PCIDevice *dev, const PCIEAERMsg *msg)
static void pcie_aer_update_log(PCIDevice *dev, const PCIEAERErr *err)
{
uint8_t *aer_cap = dev->config + dev->exp.aer_cap;
- uint8_t first_bit = ffs(err->status) - 1;
+ uint8_t first_bit = ctz32(err->status);
uint32_t errcap = pci_get_long(aer_cap + PCI_ERR_CAP);
int i;
diff --git a/hw/pci/shpc.c b/hw/pci/shpc.c
index 759910f..a706486 100644
--- a/hw/pci/shpc.c
+++ b/hw/pci/shpc.c
@@ -61,7 +61,7 @@
/* Same slot state masks are used for command and status registers */
#define SHPC_SLOT_STATE_MASK 0x03
#define SHPC_SLOT_STATE_SHIFT \
- (ffs(SHPC_SLOT_STATE_MASK) - 1)
+ ctz32(SHPC_SLOT_STATE_MASK)
#define SHPC_STATE_NO 0x0
#define SHPC_STATE_PWRONLY 0x1
@@ -70,10 +70,10 @@
#define SHPC_SLOT_PWR_LED_MASK 0xC
#define SHPC_SLOT_PWR_LED_SHIFT \
- (ffs(SHPC_SLOT_PWR_LED_MASK) - 1)
+ ctz32(SHPC_SLOT_PWR_LED_MASK)
#define SHPC_SLOT_ATTN_LED_MASK 0x30
#define SHPC_SLOT_ATTN_LED_SHIFT \
- (ffs(SHPC_SLOT_ATTN_LED_MASK) - 1)
+ ctz32(SHPC_SLOT_ATTN_LED_MASK)
#define SHPC_LED_NO 0x0
#define SHPC_LED_ON 0x1
@@ -136,7 +136,7 @@ static int roundup_pow_of_two(int x)
static uint16_t shpc_get_status(SHPCDevice *shpc, int slot, uint16_t msk)
{
uint8_t *status = shpc->config + SHPC_SLOT_STATUS(slot);
- return (pci_get_word(status) & msk) >> (ffs(msk) - 1);
+ return (pci_get_word(status) & msk) >> ctz32(msk);
}
static void shpc_set_status(SHPCDevice *shpc,
@@ -144,7 +144,7 @@ static void shpc_set_status(SHPCDevice *shpc,
{
uint8_t *status = shpc->config + SHPC_SLOT_STATUS(slot);
pci_word_test_and_clear_mask(status, msk);
- pci_word_test_and_set_mask(status, value << (ffs(msk) - 1));
+ pci_word_test_and_set_mask(status, value << ctz32(msk));
}
static void shpc_interrupt_update(PCIDevice *d)
diff --git a/hw/pci/slotid_cap.c b/hw/pci/slotid_cap.c
index 62f7bae..1c01d34 100644
--- a/hw/pci/slotid_cap.c
+++ b/hw/pci/slotid_cap.c
@@ -3,7 +3,7 @@
#include "qemu/error-report.h"
#define SLOTID_CAP_LENGTH 4
-#define SLOTID_NSLOTS_SHIFT (ffs(PCI_SID_ESR_NSLOTS) - 1)
+#define SLOTID_NSLOTS_SHIFT ctz32(PCI_SID_ESR_NSLOTS)
int slotid_cap_init(PCIDevice *d, int nslots,
uint8_t chassis,
diff --git a/hw/ppc/ppce500_spin.c b/hw/ppc/ppce500_spin.c
index d49f2b8..a99f7b0 100644
--- a/hw/ppc/ppce500_spin.c
+++ b/hw/ppc/ppce500_spin.c
@@ -74,7 +74,7 @@ static void spin_reset(void *opaque)
/* Create -kernel TLB entries for BookE, linearly spanning 256MB. */
static inline hwaddr booke206_page_size_to_tlb(uint64_t size)
{
- return (ffs(size >> 10) - 1) >> 1;
+ return ctz32(size >> 10) >> 1;
}
static void mmubooke_create_initial_mapping(CPUPPCState *env,
diff --git a/hw/scsi/megasas.c b/hw/scsi/megasas.c
index bf83b65..5ce39da 100644
--- a/hw/scsi/megasas.c
+++ b/hw/scsi/megasas.c
@@ -807,7 +807,7 @@ static int megasas_ctrl_get_info(MegasasState *s, MegasasCmd *cmd)
MFI_INFO_LDOPS_READ_POLICY);
info.max_strips_per_io = cpu_to_le16(s->fw_sge);
info.stripe_sz_ops.min = 3;
- info.stripe_sz_ops.max = ffs(MEGASAS_MAX_SECTORS + 1) - 1;
+ info.stripe_sz_ops.max = ctz32(MEGASAS_MAX_SECTORS + 1);
info.properties.pred_fail_poll_interval = cpu_to_le16(300);
info.properties.intr_throttle_cnt = cpu_to_le16(16);
info.properties.intr_throttle_timeout = cpu_to_le16(50);
diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
index be2d9b8..f669d5c 100644
--- a/include/hw/pci/pci.h
+++ b/include/hw/pci/pci.h
@@ -568,7 +568,7 @@ static inline void
pci_set_byte_by_mask(uint8_t *config, uint8_t mask, uint8_t reg)
{
uint8_t val = pci_get_byte(config);
- uint8_t rval = reg << (ffs(mask) - 1);
+ uint8_t rval = reg << ctz32(mask);
pci_set_byte(config, (~mask & val) | (mask & rval));
}
@@ -576,14 +576,14 @@ static inline uint8_t
pci_get_byte_by_mask(uint8_t *config, uint8_t mask)
{
uint8_t val = pci_get_byte(config);
- return (val & mask) >> (ffs(mask) - 1);
+ return (val & mask) >> ctz32(mask);
}
static inline void
pci_set_word_by_mask(uint8_t *config, uint16_t mask, uint16_t reg)
{
uint16_t val = pci_get_word(config);
- uint16_t rval = reg << (ffs(mask) - 1);
+ uint16_t rval = reg << ctz32(mask);
pci_set_word(config, (~mask & val) | (mask & rval));
}
@@ -591,14 +591,14 @@ static inline uint16_t
pci_get_word_by_mask(uint8_t *config, uint16_t mask)
{
uint16_t val = pci_get_word(config);
- return (val & mask) >> (ffs(mask) - 1);
+ return (val & mask) >> ctz32(mask);
}
static inline void
pci_set_long_by_mask(uint8_t *config, uint32_t mask, uint32_t reg)
{
uint32_t val = pci_get_long(config);
- uint32_t rval = reg << (ffs(mask) - 1);
+ uint32_t rval = reg << ctz32(mask);
pci_set_long(config, (~mask & val) | (mask & rval));
}
@@ -606,14 +606,14 @@ static inline uint32_t
pci_get_long_by_mask(uint8_t *config, uint32_t mask)
{
uint32_t val = pci_get_long(config);
- return (val & mask) >> (ffs(mask) - 1);
+ return (val & mask) >> ctz32(mask);
}
static inline void
pci_set_quad_by_mask(uint8_t *config, uint64_t mask, uint64_t reg)
{
uint64_t val = pci_get_quad(config);
- uint64_t rval = reg << (ffs(mask) - 1);
+ uint64_t rval = reg << ctz32(mask);
pci_set_quad(config, (~mask & val) | (mask & rval));
}
@@ -621,7 +621,7 @@ static inline uint64_t
pci_get_quad_by_mask(uint8_t *config, uint64_t mask)
{
uint64_t val = pci_get_quad(config);
- return (val & mask) >> (ffs(mask) - 1);
+ return (val & mask) >> ctz32(mask);
}
PCIDevice *pci_create_multifunction(PCIBus *bus, int devfn, bool multifunction,
diff --git a/include/hw/pci/pcie_regs.h b/include/hw/pci/pcie_regs.h
index 652d9fc..85e53e5 100644
--- a/include/hw/pci/pcie_regs.h
+++ b/include/hw/pci/pcie_regs.h
@@ -27,34 +27,34 @@
/* PCI_EXP_FLAGS */
#define PCI_EXP_FLAGS_VER2 2 /* for now, supports only ver. 2 */
-#define PCI_EXP_FLAGS_IRQ_SHIFT (ffs(PCI_EXP_FLAGS_IRQ) - 1)
-#define PCI_EXP_FLAGS_TYPE_SHIFT (ffs(PCI_EXP_FLAGS_TYPE) - 1)
+#define PCI_EXP_FLAGS_IRQ_SHIFT ctz32(PCI_EXP_FLAGS_IRQ)
+#define PCI_EXP_FLAGS_TYPE_SHIFT ctz32(PCI_EXP_FLAGS_TYPE)
/* PCI_EXP_LINK{CAP, STA} */
/* link speed */
#define PCI_EXP_LNK_LS_25 1
-#define PCI_EXP_LNK_MLW_SHIFT (ffs(PCI_EXP_LNKCAP_MLW) - 1)
+#define PCI_EXP_LNK_MLW_SHIFT ctz32(PCI_EXP_LNKCAP_MLW)
#define PCI_EXP_LNK_MLW_1 (1 << PCI_EXP_LNK_MLW_SHIFT)
/* PCI_EXP_LINKCAP */
-#define PCI_EXP_LNKCAP_ASPMS_SHIFT (ffs(PCI_EXP_LNKCAP_ASPMS) - 1)
+#define PCI_EXP_LNKCAP_ASPMS_SHIFT ctz32(PCI_EXP_LNKCAP_ASPMS)
#define PCI_EXP_LNKCAP_ASPMS_0S (1 << PCI_EXP_LNKCAP_ASPMS_SHIFT)
-#define PCI_EXP_LNKCAP_PN_SHIFT (ffs(PCI_EXP_LNKCAP_PN) - 1)
+#define PCI_EXP_LNKCAP_PN_SHIFT ctz32(PCI_EXP_LNKCAP_PN)
-#define PCI_EXP_SLTCAP_PSN_SHIFT (ffs(PCI_EXP_SLTCAP_PSN) - 1)
+#define PCI_EXP_SLTCAP_PSN_SHIFT ctz32(PCI_EXP_SLTCAP_PSN)
#define PCI_EXP_SLTCTL_IND_RESERVED 0x0
#define PCI_EXP_SLTCTL_IND_ON 0x1
#define PCI_EXP_SLTCTL_IND_BLINK 0x2
#define PCI_EXP_SLTCTL_IND_OFF 0x3
-#define PCI_EXP_SLTCTL_AIC_SHIFT (ffs(PCI_EXP_SLTCTL_AIC) - 1)
+#define PCI_EXP_SLTCTL_AIC_SHIFT ctz32(PCI_EXP_SLTCTL_AIC)
#define PCI_EXP_SLTCTL_AIC_OFF \
(PCI_EXP_SLTCTL_IND_OFF << PCI_EXP_SLTCTL_AIC_SHIFT)
-#define PCI_EXP_SLTCTL_PIC_SHIFT (ffs(PCI_EXP_SLTCTL_PIC) - 1)
+#define PCI_EXP_SLTCTL_PIC_SHIFT ctz32(PCI_EXP_SLTCTL_PIC)
#define PCI_EXP_SLTCTL_PIC_OFF \
(PCI_EXP_SLTCTL_IND_OFF << PCI_EXP_SLTCTL_PIC_SHIFT)
#define PCI_EXP_SLTCTL_PIC_ON \
@@ -109,7 +109,7 @@
#define PCI_ERR_ROOT_IRQ_MAX 32
#define PCI_ERR_ROOT_IRQ 0xf8000000
-#define PCI_ERR_ROOT_IRQ_SHIFT (ffs(PCI_ERR_ROOT_IRQ) - 1)
+#define PCI_ERR_ROOT_IRQ_SHIFT ctz32(PCI_ERR_ROOT_IRQ)
#define PCI_ERR_ROOT_STATUS_REPORT_MASK (PCI_ERR_ROOT_COR_RCV | \
PCI_ERR_ROOT_MULTI_COR_RCV | \
PCI_ERR_ROOT_UNCOR_RCV | \
diff --git a/target-ppc/cpu.h b/target-ppc/cpu.h
index f15815f..c05c503 100644
--- a/target-ppc/cpu.h
+++ b/target-ppc/cpu.h
@@ -2251,8 +2251,8 @@ static inline ppcmas_tlb_t *booke206_get_tlbm(CPUPPCState *env, const int tlbn,
{
int r;
uint32_t ways = booke206_tlb_ways(env, tlbn);
- int ways_bits = ffs(ways) - 1;
- int tlb_bits = ffs(booke206_tlb_size(env, tlbn)) - 1;
+ int ways_bits = ctz32(ways);
+ int tlb_bits = ctz32(booke206_tlb_size(env, tlbn));
int i;
way &= ways - 1;
--
2.1.0
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [Qemu-devel] [PATCH v2 5/9] Convert ffs() != 0 callers to ctz32()
2015-03-17 15:09 [Qemu-devel] [PATCH v2 0/9] Convert ffs(3) to ctz32() Stefan Hajnoczi
` (3 preceding siblings ...)
2015-03-17 15:09 ` [Qemu-devel] [PATCH v2 4/9] Convert (ffs(val) - 1) to ctz32(val) Stefan Hajnoczi
@ 2015-03-17 15:09 ` Stefan Hajnoczi
2015-03-17 15:09 ` [Qemu-devel] [PATCH v2 6/9] sd: convert sd_normal_command() ffs(3) call " Stefan Hajnoczi
` (3 subsequent siblings)
8 siblings, 0 replies; 10+ messages in thread
From: Stefan Hajnoczi @ 2015-03-17 15:09 UTC (permalink / raw)
To: qemu-devel; +Cc: Peter Maydell, Markus Armbruster, Stefan Hajnoczi
There are a number of ffs(3) callers that do roughly:
bit = ffs(val);
if (bit) {
do_something(bit - 1);
}
This pattern can be converted to ctz32() like this:
zeroes = ctz32(val);
if (zeroes != 32) {
do_something(zeroes);
}
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
hw/arm/omap1.c | 6 ++----
hw/char/virtio-serial-bus.c | 8 ++++----
hw/gpio/omap_gpio.c | 13 +++++--------
hw/i2c/omap_i2c.c | 10 +++++++---
hw/intc/allwinner-a10-pic.c | 8 ++++----
kvm-all.c | 8 ++++----
6 files changed, 26 insertions(+), 27 deletions(-)
diff --git a/hw/arm/omap1.c b/hw/arm/omap1.c
index abb183c..fbd4695 100644
--- a/hw/arm/omap1.c
+++ b/hw/arm/omap1.c
@@ -1989,8 +1989,7 @@ static void omap_mpuio_write(void *opaque, hwaddr addr,
case 0x04: /* OUTPUT_REG */
diff = (s->outputs ^ value) & ~s->dir;
s->outputs = value;
- while ((ln = ffs(diff))) {
- ln --;
+ while ((ln = ctz32(diff)) != 32) {
if (s->handler[ln])
qemu_set_irq(s->handler[ln], (value >> ln) & 1);
diff &= ~(1 << ln);
@@ -2002,8 +2001,7 @@ static void omap_mpuio_write(void *opaque, hwaddr addr,
s->dir = value;
value = s->outputs & ~s->dir;
- while ((ln = ffs(diff))) {
- ln --;
+ while ((ln = ctz32(diff)) != 32) {
if (s->handler[ln])
qemu_set_irq(s->handler[ln], (value >> ln) & 1);
diff &= ~(1 << ln);
diff --git a/hw/char/virtio-serial-bus.c b/hw/char/virtio-serial-bus.c
index c86814f..17273a8 100644
--- a/hw/char/virtio-serial-bus.c
+++ b/hw/char/virtio-serial-bus.c
@@ -783,12 +783,12 @@ static uint32_t find_free_port_id(VirtIOSerial *vser)
max_nr_ports = vser->serial.max_virtserial_ports;
for (i = 0; i < (max_nr_ports + 31) / 32; i++) {
- uint32_t map, bit;
+ uint32_t map, zeroes;
map = vser->ports_map[i];
- bit = ffs(~map);
- if (bit) {
- return (bit - 1) + i * 32;
+ zeroes = ctz32(~map);
+ if (zeroes != 32) {
+ return zeroes + i * 32;
}
}
return VIRTIO_CONSOLE_BAD_ID;
diff --git a/hw/gpio/omap_gpio.c b/hw/gpio/omap_gpio.c
index 938782a..78c2436 100644
--- a/hw/gpio/omap_gpio.c
+++ b/hw/gpio/omap_gpio.c
@@ -124,8 +124,7 @@ static void omap_gpio_write(void *opaque, hwaddr addr,
case 0x04: /* DATA_OUTPUT */
diff = (s->outputs ^ value) & ~s->dir;
s->outputs = value;
- while ((ln = ffs(diff))) {
- ln --;
+ while ((ln = ctz32(diff)) != 32) {
if (s->handler[ln])
qemu_set_irq(s->handler[ln], (value >> ln) & 1);
diff &= ~(1 << ln);
@@ -137,8 +136,7 @@ static void omap_gpio_write(void *opaque, hwaddr addr,
s->dir = value;
value = s->outputs & ~s->dir;
- while ((ln = ffs(diff))) {
- ln --;
+ while ((ln = ctz32(diff)) != 32) {
if (s->handler[ln])
qemu_set_irq(s->handler[ln], (value >> ln) & 1);
diff &= ~(1 << ln);
@@ -252,8 +250,7 @@ static inline void omap2_gpio_module_out_update(struct omap2_gpio_s *s,
s->outputs ^= diff;
diff &= ~s->dir;
- while ((ln = ffs(diff))) {
- ln --;
+ while ((ln = ctz32(diff)) != 32) {
qemu_set_irq(s->handler[ln], (s->outputs >> ln) & 1);
diff &= ~(1 << ln);
}
@@ -441,8 +438,8 @@ static void omap2_gpio_module_write(void *opaque, hwaddr addr,
s->dir = value;
value = s->outputs & ~s->dir;
- while ((ln = ffs(diff))) {
- diff &= ~(1 <<-- ln);
+ while ((ln = ctz32(diff)) != 32) {
+ diff &= ~(1 << ln);
qemu_set_irq(s->handler[ln], (value >> ln) & 1);
}
diff --git a/hw/i2c/omap_i2c.c b/hw/i2c/omap_i2c.c
index d63278d..b6f544a 100644
--- a/hw/i2c/omap_i2c.c
+++ b/hw/i2c/omap_i2c.c
@@ -171,9 +171,13 @@ static uint32_t omap_i2c_read(void *opaque, hwaddr addr)
case 0x0c: /* I2C_IV */
if (s->revision >= OMAP2_INTR_REV)
break;
- ret = ffs(s->stat & s->mask);
- if (ret)
- s->stat ^= 1 << (ret - 1);
+ ret = ctz32(s->stat & s->mask);
+ if (ret != 32) {
+ s->stat ^= 1 << ret;
+ ret++;
+ } else {
+ ret = 0;
+ }
omap_i2c_interrupts_update(s);
return ret;
diff --git a/hw/intc/allwinner-a10-pic.c b/hw/intc/allwinner-a10-pic.c
index de820b9..eed7621 100644
--- a/hw/intc/allwinner-a10-pic.c
+++ b/hw/intc/allwinner-a10-pic.c
@@ -23,7 +23,7 @@
static void aw_a10_pic_update(AwA10PICState *s)
{
uint8_t i;
- int irq = 0, fiq = 0, pending;
+ int irq = 0, fiq = 0, zeroes;
s->vector = 0;
@@ -32,9 +32,9 @@ static void aw_a10_pic_update(AwA10PICState *s)
fiq |= s->select[i] & s->irq_pending[i] & ~s->mask[i];
if (!s->vector) {
- pending = ffs(s->irq_pending[i] & ~s->mask[i]);
- if (pending) {
- s->vector = (i * 32 + pending - 1) * 4;
+ zeroes = ctz32(s->irq_pending[i] & ~s->mask[i]);
+ if (zeroes != 32) {
+ s->vector = (i * 32 + zeroes) * 4;
}
}
}
diff --git a/kvm-all.c b/kvm-all.c
index 55025cc..003312f 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -1121,18 +1121,18 @@ static int kvm_irqchip_get_virq(KVMState *s)
{
uint32_t *word = s->used_gsi_bitmap;
int max_words = ALIGN(s->gsi_count, 32) / 32;
- int i, bit;
+ int i, zeroes;
bool retry = true;
again:
/* Return the lowest unused GSI in the bitmap */
for (i = 0; i < max_words; i++) {
- bit = ffs(~word[i]);
- if (!bit) {
+ zeroes = ctz32(~word[i]);
+ if (zeroes == 32) {
continue;
}
- return bit - 1 + i * 32;
+ return zeroes + i * 32;
}
if (!s->direct_msi && retry) {
retry = false;
--
2.1.0
^ permalink raw reply related [flat|nested] 10+ messages in thread