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authorH. Peter Anvin <hpa@zytor.com>2007-09-21 16:52:35 -0700
committerH. Peter Anvin <hpa@zytor.com>2007-09-21 16:52:35 -0700
commit5a16eeb519c87fa4c437e838af81731b8d355052 (patch)
treef59258a720429d5ad8beaf2070f73cab6a187077 /memdump/__udivmoddi4.c
parent31daeb2ddb972dc70b929da1c93288e821c87ed7 (diff)
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memdump: a debugging utility to dump memory over a serial port
A memory-dumping utility which runs in real mode. Thus, it can be used to get memory dumps from a relatively pristine system.
Diffstat (limited to 'memdump/__udivmoddi4.c')
-rw-r--r--memdump/__udivmoddi4.c31
1 files changed, 31 insertions, 0 deletions
diff --git a/memdump/__udivmoddi4.c b/memdump/__udivmoddi4.c
new file mode 100644
index 00000000..8e7661f5
--- /dev/null
+++ b/memdump/__udivmoddi4.c
@@ -0,0 +1,31 @@
+#include <stdint.h>
+
+uint64_t __udivmoddi4(uint64_t num, uint64_t den, uint64_t *rem_p)
+{
+ uint64_t quot = 0, qbit = 1;
+
+ if ( den == 0 ) {
+ asm volatile("int $0");
+ return 0; /* If trap returns... */
+ }
+
+ /* Left-justify denominator and count shift */
+ while ( (int64_t)den >= 0 ) {
+ den <<= 1;
+ qbit <<= 1;
+ }
+
+ while ( qbit ) {
+ if ( den <= num ) {
+ num -= den;
+ quot += qbit;
+ }
+ den >>= 1;
+ qbit >>= 1;
+ }
+
+ if ( rem_p )
+ *rem_p = num;
+
+ return quot;
+}