search for: subceil_s

hi all I have a question about implementing a new instruction which does this function f(x) = x + ceilf (x) .x is a single float i have already added the instruction in my backend in the .td file def SUBCEIL_S : FFR<0x11, 0x3, 16, (outs FGR32:$fd), (ins FGR32:$fs), "frac.s\t$fd, $fs", [(set (f32 FGR32:$fd), (fadd (f32 FGR32:$fs ),(f32 (ceilf FGR32:$fs))))] >; it makes and install correctly but when i ll try to write code to use this instruction there is no luck. Should i do someth...

Hi, > def SUBCEIL_S : FFR<0x11, 0x3, 16, (outs FGR32:$fd), (ins FGR32:$fs), > "frac.s\t$fd, $fs", [(set (f32 FGR32:$fd), (fadd (f32 FGR32:$fs ),(f32 > (ceilf FGR32:$fs))))] >; > > it makes and install correctly but when i ll try to write code to use this > instruction there is no l...

Hi, > i ve uploaded .ll file Is that the C file that's at the end of your message? To produce a .ll file, you give clang the "-emit-llvm" option (and probably "-S"). Anyway, what I see in the C you posted is that Clang is using constant folding to avoid doing any of the operations you've requested. A better C file test would be: float foo(float d) { return d -

>I'm also a little worried that your pattern has fadd, but your C >source has a subtraction. :S i wrote it wrong the true implementation is def SUBCEIL_S : FFR<0x11, 0x3, 16, (outs FGR32:$fd), (ins FGR32:$fs), "frac.s\t$fd, $fs", [(set (f32 FGR32:$fd), (fsub (f32 FGR32:$fs ),(f32 (ceilf FGR32:$fs))))] >; I use some C,C++ code to test my backend. i use clang with those argument -m32 -emit-llvm -S -target mipsel-linux-gnu...

Hi and thanks for answering llc works fine just does not selecting my instruction i ve uploaded .ll file how can i include this attribute "readonly" so i can see if changes the generated assembly? my code is very simple int main (){ float d, d1 ; d= 12.3; d1 = d - ceilf(d); return 0; } -- View this message in context: