summaryrefslogtreecommitdiffstats
path: root/qemu/roms/ipxe/src/arch/i386/include/bits/strings.h
diff options
context:
space:
mode:
authorJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-05-18 13:18:31 +0300
committerJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-05-18 13:42:15 +0300
commit437fd90c0250dee670290f9b714253671a990160 (patch)
treeb871786c360704244a07411c69fb58da9ead4a06 /qemu/roms/ipxe/src/arch/i386/include/bits/strings.h
parent5bbd6fe9b8bab2a93e548c5a53b032d1939eec05 (diff)
These changes are the raw update to qemu-2.6.
Collission happened in the following patches: migration: do cleanup operation after completion(738df5b9) Bug fix.(1750c932f86) kvmclock: add a new function to update env->tsc.(b52baab2) The code provided by the patches was already in the upstreamed version. Change-Id: I3cc11841a6a76ae20887b2e245710199e1ea7f9a Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'qemu/roms/ipxe/src/arch/i386/include/bits/strings.h')
-rw-r--r--qemu/roms/ipxe/src/arch/i386/include/bits/strings.h48
1 files changed, 46 insertions, 2 deletions
diff --git a/qemu/roms/ipxe/src/arch/i386/include/bits/strings.h b/qemu/roms/ipxe/src/arch/i386/include/bits/strings.h
index 092bcb593..453545f00 100644
--- a/qemu/roms/ipxe/src/arch/i386/include/bits/strings.h
+++ b/qemu/roms/ipxe/src/arch/i386/include/bits/strings.h
@@ -1,7 +1,51 @@
#ifndef _BITS_STRINGS_H
#define _BITS_STRINGS_H
-FILE_LICENCE ( GPL2_OR_LATER );
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
+
+/**
+ * Find first (i.e. least significant) set bit
+ *
+ * @v value Value
+ * @ret lsb Least significant bit set in value (LSB=1), or zero
+ */
+static inline __attribute__ (( always_inline )) int __ffsl ( long value ) {
+ long lsb_minus_one;
+
+ /* If the input value is zero, the BSF instruction returns
+ * ZF=0 and leaves an undefined value in the output register.
+ * Perform this check in C rather than asm so that it can be
+ * omitted in cases where the compiler is able to prove that
+ * the input is non-zero.
+ */
+ if ( value ) {
+ __asm__ ( "bsfl %1, %0"
+ : "=r" ( lsb_minus_one )
+ : "rm" ( value ) );
+ return ( lsb_minus_one + 1 );
+ } else {
+ return 0;
+ }
+}
+
+/**
+ * Find first (i.e. least significant) set bit
+ *
+ * @v value Value
+ * @ret lsb Least significant bit set in value (LSB=1), or zero
+ */
+static inline __attribute__ (( always_inline )) int __ffsll ( long long value ){
+ unsigned long high = ( value >> 32 );
+ unsigned long low = ( value >> 0 );
+
+ if ( low ) {
+ return ( __ffsl ( low ) );
+ } else if ( high ) {
+ return ( 32 + __ffsl ( high ) );
+ } else {
+ return 0;
+ }
+}
/**
* Find last (i.e. most significant) set bit
@@ -13,7 +57,7 @@ static inline __attribute__ (( always_inline )) int __flsl ( long value ) {
long msb_minus_one;
/* If the input value is zero, the BSR instruction returns
- * ZF=1 and leaves an undefined value in the output register.
+ * ZF=0 and leaves an undefined value in the output register.
* Perform this check in C rather than asm so that it can be
* omitted in cases where the compiler is able to prove that
* the input is non-zero.