https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120638
--- Comment #2 from chenglulu <chenglulu at loongson dot cn> --- I compared the test.c.141t.dom2 and testf.c.208t.dom3 dom2： ``` range_of_expr (_5) [frange] float [1.0e+0 (0x0.8p+1), 6.5536e+4 (0x0.8p+17)] range_of_expr (_6) [frange] float [7.62939453125e-6 (0x0.8p-16), 5.0e-1 (0x0.8p+0)] ... step.0_1 = step; _2 = (double) step.0_1; _3 = _2 + 1.0e+0; _4 = (float) _3; _5 = sqrtf (_4); _6 = 5.0e-1 / _5; test1 (_6); ``` I think the range of _5 and _6 in dom2 is correct. dom3: ``` range_of_expr (_5) [frange] float [1.0e+0 (0x0.8p+1), 6.5536e+4 (0x0.8p+17)] range_of_expr (_6) [frange] float [5.0e-1 (0x0.8p+0), 5.0e-1 (0x0.8p+0)] ... step.0_1 = step; _2 = (double) step.0_1; _3 = _2 + 1.0e+0; _4 = (float) _3; _5 = .RSQRT (_4); _6 = _5 * 5.0e-1; test1 (5.0e-1); ``` But in dom3, the range of _5 is wrong. The error is caused by the calculation of the range of .RSQRT(_4) is [-0.0, +Inf]. This result intersects with the range of _5 calculated in the previous optimization pass ,and we get [1.0e+0 (0x0.8p+1), 6.5536e+4 (0x0.8p+17)]. Then use the range of _5 to calculate the range of _6, which is [5.0e-1 (0x0.8p+0),3.2768e+4]. Then take the intersection again, the range of _6 is [5.0e-1 (0x0.8p+0), 5.0e-1 (0x0.8p+0)].
