The tier checks a number finite in integers (its exponent's bits all ones), off the number pipes the divisions and sums wait on: roots 10.9 to 9.6 ms (1.39x C). 040 newton.c: roots' loop in the forms the tier may make it (the check as numbers 9.7 ms, in integers 8.7, none 7.7; next in r's register as gcc keeps it 7.0)

1 files changed, 6 insertions, 4 deletions

diff --git a/core/module-jit.c b/core/module-jit.c
index 43441b1..7110a19 100644
--- a/core/module-jit.c
+++ b/core/module-jit.c
@@ -4646,10 +4646,12 @@ static void tsmall_from_0(Tier *t, unsigned r, int fail) {
 }
 
 /* A number in d finite, else to fail. */
-static void tfinite_check(Tier *t, unsigned d, int fail) {
-    fp2(t->k->e, FABS, D2, d);
-    fcmp(t->k->e, D2, D8);
-    b_cond(t->k->e, HS, fail);
+static void tfinite_check(Tier *t, unsigned d, int fail) { /* its exponent's bits all ones: not finite (in integers: off the number pipes, 040 newton.c) */
+    Emit *e = t->k->e;
+    fp2(e, FMOV_XD, X10, d);
+    put(e, 0xD374F800 | X10 << 5 | X10); /* UBFX x10, x10, #52, #11 */
+    cmp_imm(e, X10, 0x7FF);
+    b_cond(e, EQ, fail);
 }
 
 /* Affine value x of loop l at the round in register kr (XZR: round 0)