sim: Clean up some constants used in some syscalls.

Having readable constants for these large numbers is good, but they
used incorrect style, were at global scope, and were only used in one
place.

This change centralizes them where they're used, fixes their style, and
rewrites the actual constants in a way that makes it clear what they're
values are.

Change-Id: Ib89c46fce133d4180296d384a61d51d1fe1f8d20
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/23455
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Maintainer: Gabe Black <gabeblack@google.com>

diff --git a/src/sim/syscall_emul.hh b/src/sim/syscall_emul.hh
index 74ffd761fcdbe54ef0844d8fd1c7b1cf390693d0..0bc846a7a08f16f1b05d2a633032a06cce186c27 100644 (file)
--- a/src/sim/syscall_emul.hh
+++ b/src/sim/syscall_emul.hh
@@ -508,15 +508,10 @@ futexFunc(SyscallDesc *desc, int callnum, ThreadContext *tc,
 SyscallReturn pipePseudoFunc(SyscallDesc *desc, int num, ThreadContext *tc);
 
 
-/// A readable name for 1,000,000, for converting microseconds to seconds.
-const int one_million = 1000000;
-/// A readable name for 1,000,000,000, for converting nanoseconds to seconds.
-const int one_billion = 1000000000;
-
 /// Approximate seconds since the epoch (1/1/1970).  About a billion,
 /// by my reckoning.  We want to keep this a constant (not use the
 /// real-world time) to keep simulations repeatable.
-const unsigned seconds_since_epoch = 1000000000;
+const unsigned seconds_since_epoch = 1000 * 1000 * 1000;
 
 /// Helper function to convert current elapsed time to seconds and
 /// microseconds.
@@ -524,9 +519,11 @@ template <class T1, class T2>
 void
 getElapsedTimeMicro(T1 &sec, T2 &usec)
 {
+    static const int OneMillion = 1000 * 1000;
+
     uint64_t elapsed_usecs = curTick() / SimClock::Int::us;
-    sec = elapsed_usecs / one_million;
-    usec = elapsed_usecs % one_million;
+    sec = elapsed_usecs / OneMillion;
+    usec = elapsed_usecs % OneMillion;
 }
 
 /// Helper function to convert current elapsed time to seconds and
@@ -535,9 +532,11 @@ template <class T1, class T2>
 void
 getElapsedTimeNano(T1 &sec, T2 &nsec)
 {
+    static const int OneBillion = 1000 * 1000 * 1000;
+
     uint64_t elapsed_nsecs = curTick() / SimClock::Int::ns;
-    sec = elapsed_nsecs / one_billion;
-    nsec = elapsed_nsecs % one_billion;
+    sec = elapsed_nsecs / OneBillion;
+    nsec = elapsed_nsecs % OneBillion;
 }
 
 //////////////////////////////////////////////////////////////////////