Add benchmark tests for slowpow and slowexp

Separate benchmarks for the fast and slow implementations of pow and
exp since measuring both together doesn't make sense.  Adjust the
iterations for pow and exp accordingly so that they run long enough
for the measurements to be meaningful.

1 files changed, 22 insertions, 4 deletions

diff --git a/benchtests/Makefile b/benchtests/Makefile
index cc54b81faa..b3dfbff971 100644
--- a/benchtests/Makefile
+++ b/benchtests/Makefile
@@ -25,7 +25,9 @@
 
 # - Define foo-ITER with the number of iterations you want to run.  Keep it
 #   high enough that the overhead of clock_gettime is only a small fraction of
-#   the total run time of the test.
+#   the total run time of the test.  A good idea would be to keep the run time
+#   of each test at around 10 seconds for x86_64.  That is just a guideline,
+#   since some scenarios may require higher run times.
 
 # - Define foo-ARGLIST as a colon separated list of types of the input
 #   arguments.  Use `void` if function does not take any inputs.  Put in quotes
@@ -43,14 +45,16 @@
 #   See pow-inputs for an example.
 
 subdir := benchtests
-bench := exp pow rint
+bench := exp pow rint slowexp slowpow
 
-exp-ITER = 100000
+# exp function fast path
+exp-ITER = 5e8
 exp-ARGLIST = double
 exp-RET = double
 LDFLAGS-bench-exp = -lm
 
-pow-ITER = 100000
+# pow function fast path
+pow-ITER = 2e8
 pow-ARGLIST = double:double
 pow-RET = double
 LDFLAGS-bench-pow = -lm
@@ -60,5 +64,19 @@ rint-ARGLIST = double
 rint-RET = double
 LDFLAGS-bench-rint = -lm
 
+# exp function slowest path
+slowexp-ITER = 3e5
+slowexp-ARGLIST = double
+slowexp-RET = double
+slowexp-INCLUDE = slowexp.c
+LDFLAGS-bench-slowexp = -lm
+
+# pow function slowest path
+slowpow-ITER = 1e5
+slowpow-ARGLIST = double:double
+slowpow-RET = double
+slowpow-INCLUDE = slowpow.c
+LDFLAGS-bench-slowpow = -lm
+
 include ../Makeconfig
 include ../Rules