[PATCH] Speed up math/test-tgmath2.c

[Steve Ellcey <sellcey at caviumnetworks dot com>]

The test math/test-tgmath2.c takes a long time to compile with newer
versions of GCC due to variable tracking.  There was some discussion a
while back about using -fno-var-tracking on this test but that was not
considered to be the correct solution, it was thought that breaking up
the test into smaller pieces in order to speed up compilation was a
better solution.  Here is a patch that does that.  It does not break it
up into multiple tests but it breaks up the test function into multiple
functions so that there isn't one single giant function that gives the
GCC variable tracking phase a fit.

On a box where the original version takes 18 minutes to compile using a
pre-release GCC 7.0, the modified version compiles in 3 minutes.  GCC
5.4 took about 2.5 minutes on the same machine.

Original discussion:

https://sourceware.org/ml/libc-alpha/2012-10/msg00430.html


Does this seem like a reasonable way to speed up this test?


2016-10-24  Steve Ellcey  <sellcey@caviumnetworks.com>

        * math/test-tgmath2.c: Split up test function.


diff --git a/math/test-tgmath2.c b/math/test-tgmath2.c
index b376fd6..4d828fe 100644
--- a/math/test-tgmath2.c
+++ b/math/test-tgmath2.c
@@ -89,12 +89,6 @@ enum
 int count;
 int counts[Tlast][C_last];
 
-int
-test (const int Vint4, const long long int Vllong4)
-{
-  int result = 0;
-  int quo = 0;
-
 #define FAIL(str) \
   do								\
     {								\
@@ -138,6 +132,11 @@ test (const int Vint4, const long long int Vllong4)
   while (0)
 #define TEST(expr, type, fn) TEST2(expr, type, type, fn)
 
+int
+test_cos (const int Vint4, const long long int Vllong4)
+{
+  int result = 0;
+
   TEST (cos (vfloat1), float, cos);
   TEST (cos (vdouble1), double, cos);
   TEST (cos (vldouble1), ldouble, cos);
@@ -155,6 +154,14 @@ test (const int Vint4, const long long int Vllong4)
   TEST (cos (Vcdouble1), cdouble, cos);
   TEST (cos (Vcldouble1), cldouble, cos);
 
+  return result;
+}
+
+int
+test_fabs (const int Vint4, const long long int Vllong4)
+{
+  int result = 0;
+
   TEST (fabs (vfloat1), float, fabs);
   TEST (fabs (vdouble1), double, fabs);
   TEST (fabs (vldouble1), ldouble, fabs);
@@ -180,6 +187,13 @@ test (const int Vint4, const long long int Vllong4)
   TEST (fabs (Vcdouble1), double, cabs);
   TEST (fabs (Vcldouble1), ldouble, cabs);
 
+  return result;
+}
+
+int
+test_conj (const int Vint4, const long long int Vllong4)
+{
+  int result = 0;
   TEST (conj (vfloat1), cfloat, conj);
   TEST (conj (vdouble1), cdouble, conj);
   TEST (conj (vldouble1), cldouble, conj);
@@ -197,6 +211,14 @@ test (const int Vint4, const long long int Vllong4)
   TEST (conj (Vcdouble1), cdouble, conj);
   TEST (conj (Vcldouble1), cldouble, conj);
 
+  return result;
+}
+
+int
+test_expm1 (const int Vint4, const long long int Vllong4)
+{
+  int result = 0;
+
   TEST (expm1 (vfloat1), float, expm1);
   TEST (expm1 (vdouble1), double, expm1);
   TEST (expm1 (vldouble1), ldouble, expm1);
@@ -208,6 +230,13 @@ test (const int Vint4, const long long int Vllong4)
   TEST (expm1 (Vint1), double, expm1);
   TEST (expm1 (Vllong1), double, expm1);
 
+  return result;
+}
+
+int
+test_lrint (const int Vint4, const long long int Vllong4)
+{
+  int result = 0;
   TEST2 (lrint (vfloat1), float, long int, lrint);
   TEST2 (lrint (vdouble1), double, long int, lrint);
   TEST2 (lrint (vldouble1), ldouble, long int, lrint);
@@ -219,6 +248,14 @@ test (const int Vint4, const long long int Vllong4)
   TEST2 (lrint (Vint1), double, long int, lrint);
   TEST2 (lrint (Vllong1), double, long int, lrint);
 
+  return result;
+}
+
+int
+test_ldexp (const int Vint4, const long long int Vllong4)
+{
+  int result = 0;
+
   TEST (ldexp (vfloat1, 6), float, ldexp);
   TEST (ldexp (vdouble1, 6), double, ldexp);
   TEST (ldexp (vldouble1, 6), ldouble, ldexp);
@@ -230,6 +267,9 @@ test (const int Vint4, const long long int Vllong4)
   TEST (ldexp (Vint1, 6), double, ldexp);
   TEST (ldexp (Vllong1, 6), double, ldexp);
 
+  return result;
+}
+
 #define FIRST(x, y) (y, x)
 #define SECOND(x, y) (x, y)
 #define NON_LDBL_TEST(fn, argm, arg, type, fnt) \
@@ -307,25 +347,82 @@ test (const int Vint4, const long long int Vllong4)
   NON_LDBL_CTEST (fn, FIRST, Vcdouble2, cdouble, fnt); \
   NON_LDBL_CTEST (fn, SECOND, Vcdouble2, cdouble, fnt);
 
+int
+test_atan2 (const int Vint4, const long long int Vllong4)
+{
+  int result = 0;
+
   BINARY_TEST (atan2, atan2);
 
+  return result;
+}
+
+int
+test_remquo (const int Vint4, const long long int Vllong4)
+{
+  int result = 0;
+  int quo = 0;
+
 #define my_remquo(x, y) remquo (x, y, &quo)
   BINARY_TEST (my_remquo, remquo);
 #undef my_remquo
 
+  return result;
+}
+
+int
+test_pow (const int Vint4, const long long int Vllong4)
+{
+  int result = 0;
+
   BINARY_CTEST (pow, pow);
 
-  /* Testing all arguments of fma would be just too expensive,
-     so test just some.  */
+  return result;
+}
+
+/* Testing all arguments of fma would be just too expensive,
+   so test just some.  */
+
+int
+test_fma_1 (const int Vint4, const long long int Vllong4)
+{
+  int result = 0;
+
 #define my_fma(x, y) fma (x, y, vfloat3)
   BINARY_TEST (my_fma, fma);
 #undef my_fma
+
+  return result;
+}
+
+int
+test_fma_2 (const int Vint4, const long long int Vllong4)
+{
+  int result = 0;
+
 #define my_fma(x, y) fma (x, vfloat3, y)
   BINARY_TEST (my_fma, fma);
 #undef my_fma
+
+  return result;
+}
+
+int
+test_fma_3 (const int Vint4, const long long int Vllong4)
+{
+  int result = 0;
+
 #define my_fma(x, y) fma (Vfloat3, x, y)
   BINARY_TEST (my_fma, fma);
 #undef my_fma
+
+  return result;
+}
+
+int
+test_fma_4 (const int Vint4, const long long int Vllong4)
+{
+  int result = 0;
   TEST (fma (vdouble1, Vdouble2, vllong3), double, fma);
   TEST (fma (vint1, Vint2, vint3), double, fma);
   TEST (fma (Vldouble1, vldouble2, Vldouble3), ldouble, fma);
@@ -337,7 +434,19 @@ test (const int Vint4, const long long int Vllong4)
 static int
 do_test (void)
 {
-  return test (vint1, vllong1);
+  return test_cos (vint1, vllong1)
+	 + test_fabs (vint1, vllong1)
+	 + test_conj (vint1, vllong1)
+	 + test_expm1 (vint1, vllong1)
+	 + test_lrint (vint1, vllong1)
+	 + test_ldexp (vint1, vllong1)
+	 + test_atan2 (vint1, vllong1)
+	 + test_remquo (vint1, vllong1)
+	 + test_pow (vint1, vllong1)
+	 + test_fma_1 (vint1, vllong1)
+	 + test_fma_2 (vint1, vllong1)
+	 + test_fma_3 (vint1, vllong1)
+	 + test_fma_4 (vint1, vllong1);
 }
 
 /* Now generate the three functions.  */