Convert (ffs(val) - 1) to ctz32(val)

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>
Message-id: 1427124571-28598-5-git-send-email-stefanha@redhat.com
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

22 files changed, 50 insertions, 50 deletions

diff --git a/block.c b/block.c
index f2f8ae77c1..d7781eebff 100644
--- a/block.c
+++ b/block.c
@@ -5452,7 +5452,7 @@ 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 6cbae1d205..f47260b808 100644
--- a/block/qcow2-refcount.c
+++ b/block/qcow2-refcount.c
@@ -2450,7 +2450,7 @@ 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 316a8db22b..f692978a6c 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -1802,7 +1802,7 @@ 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)
     {
@@ -2110,7 +2110,7 @@ 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 892b13c806..9d908886da 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 f3ab2ddd5a..fbe87e035b 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 c14172cfa6..2d5f06a390 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 612fec03ee..77e1126f8f 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 354ccf1ea1..c89c8045c3 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 1ddea6d89c..da9fc1d51b 100644
--- a/hw/arm/strongarm.c
+++ b/hw/arm/strongarm.c
@@ -528,7 +528,7 @@ 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);
     }
 
@@ -745,7 +745,7 @@ 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 4306adc959..66b7ade8da 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 7fbf313ce8..2f59b134ee 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 94083424f8..24a77272d7 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 8134d0bcd0..3a731fe18d 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 916e1a1e5b..2949938223 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;
     }
@@ -355,12 +355,12 @@ 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 eaa3e6ea94..b48c09cd11 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 759910f79a..a706486394 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 62f7bae2f1..1c01d346c9 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 d49f2b8803..a99f7b0397 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 ad7317bfe9..91a5d97c73 100644
--- a/hw/scsi/megasas.c
+++ b/hw/scsi/megasas.c
@@ -804,7 +804,7 @@ 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 b97c2956ec..d4ffead48a 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 848ab1c206..6a28b33e69 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 f15815f11b..c05c503305 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;