@@ -3295,7 +3295,7 @@ bb_ok_for_noce_convert_multiple_sets (ba
if (count > limit)
return false;
- return count > 0;
+ return count > 1;
}
/* Given a simple IF-THEN-JOIN or IF-THEN-ELSE-JOIN block, attempt to convert
@@ -0,0 +1,70 @@
+// PR rtl-optimization/69570
+// { dg-do run }
+// { dg-options "-O2" }
+// { dg-additional-options "-fpic" { target fpic } }
+// { dg-additional-options "-march=i686" { target ia32 } }
+
+template <typename T> inline const T &
+min (const T &a, const T &b)
+{
+ if (b < a)
+ return b;
+ return a;
+}
+
+template <typename T> inline const T &
+max (const T &a, const T &b)
+{
+ if (a < b)
+ return b;
+ return a;
+}
+
+static inline void
+foo (unsigned x, unsigned y, unsigned z, double &h, double &s, double &l)
+{
+ double r = x / 255.0;
+ double g = y / 255.0;
+ double b = z / 255.0;
+ double m = max (r, max (g, b));
+ double n = min (r, min (g, b));
+ double d = m - n;
+ double e = m + n;
+ h = 0.0, s = 0.0, l = e / 2.0;
+ if (d > 0.0)
+ {
+ s = l > 0.5 ? d / (2.0 - e) : d / e;
+ if (m == r && m != g)
+ h = (g - b) / d + (g < b ? 6.0 : 0.0);
+ if (m == g && m != b)
+ h = (b - r) / d + 2.0;
+ if (m == b && m != r)
+ h = (r - g) / d + 4.0;
+ h /= 6.0;
+ }
+}
+
+__attribute__ ((noinline, noclone))
+void bar (unsigned x[3], double y[3])
+{
+ double h, s, l;
+ foo (x[0], x[1], x[2], h, s, l);
+ y[0] = h;
+ y[1] = s;
+ y[2] = l;
+}
+
+int
+main ()
+{
+ unsigned x[3] = { 0, 128, 0 };
+ double y[3];
+
+ bar (x, y);
+ if (__builtin_fabs (y[0] - 0.33333) > 0.001
+ || __builtin_fabs (y[1] - 1) > 0.001
+ || __builtin_fabs (y[2] - 0.25098) > 0.001)
+ __builtin_abort ();
+
+ return 0;
+}
Hi! While looking at this PR (which is most likely a reg-stack or RA bug triggered by the ifcvt noce_convert_multiple_sets additions), I've noticed that despite the "multiple_sets" in the name it actually attempts to handle not just multiple sets, but also the single set case, which is already handled by various calls later on noce_process_if_block. Additionally, it handles it worse than those calls we had for years, because it always creates temporary pseudos to store result into and then at the end copy back to the desired register. If there is just a single set, this temporary is unnecessary and unfortunately negatively affects RA (get larger code with more spills/fills in *.reload/postreload). So, I'd like to change noce_convert_multiple_sets to really apply to multiple sets only. While it makes the issue latent again (and I'll try to analyze it), IMHO it is the right step forward. Bootstrapped/regtested on {x86_64,i686,ppc64,ppc64le,s390,s390x,aarch64}-linux, ok for trunk? 2016-02-01 Jakub Jelinek <jakub@redhat.com> PR rtl-optimization/69570 * ifcvt.c (bb_ok_for_noce_convert_multiple_sets): Return true only if there is more than one set, not if there is a single set. * g++.dg/opt/pr69570.C: New test. Jakub