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>

1 files changed, 8 insertions, 8 deletions

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,