<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">Hi Arch<div class=""><br class=""></div><div class="">Yeah, that seems reasonable to me. LazyValueInfo seems to be more about what ranges of values control flow defines. Knowing that 'fmul float %0, %0’ is >= 0 is perfectly reasonable for SimplifyFCmpInst to know.</div><div class=""><br class=""></div><div class="">Thanks,</div><div class="">Pete<br class=""><div><blockquote type="cite" class=""><div class="">On Jan 13, 2015, at 11:27 AM, Robison, Arch <<a href="mailto:arch.robison@intel.com" class="">arch.robison@intel.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="WordSection1" style="page: WordSection1; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">After writing a simple FPRange, I've hit a stumbling block. I don't know what LLVM code should be extended to use it. I was initially thinking of extending LazyValueInfo, but it appears to be used for passes that don’t address the case that I need for Julia. I’m now wondering if I’m better off extending SimplifyFCmpInst to handle the few cases in question instead of trying to be more general. Here’s an example case for Julia where a trivially true domain check should be removed:<o:p class=""></o:p></div><div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""> </o:p></div><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">%jl_value_t = type {}<o:p class=""></o:p></div><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">@jl_domain_exception = external global %jl_value_t*<o:p class=""></o:p></div><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">declare void @jl_throw_with_superfluous_argument(%jl_value_t*, i32)<o:p class=""></o:p></div><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">declare float @llvm.sqrt.f32(float %Val)<o:p class=""></o:p></div><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""> </o:p></div><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">define float @julia_f_64805(float) {<o:p class=""></o:p></div><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">top:<o:p class=""></o:p></div><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""> %1 = fmul float %0, %0<o:p class=""></o:p></div><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""> %2 = fcmp uge float %1, 0.000000e+00<o:p class=""></o:p></div><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""> br i1 %2, label %pass, label %fail<o:p class=""></o:p></div><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""> </o:p></div><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">fail: ; preds = %top<o:p class=""></o:p></div><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""> %3 = load %jl_value_t** @jl_domain_exception, align 8<o:p class=""></o:p></div><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""> call void @jl_throw_with_superfluous_argument(%jl_value_t* %3, i32 2)<o:p class=""></o:p></div><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""> unreachable<o:p class=""></o:p></div><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""> </o:p></div><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">pass: ; preds = %top<o:p class=""></o:p></div><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""> %4 = call float @llvm.sqrt.f32(float %1)<o:p class=""></o:p></div><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""> ret float %4<o:p class=""></o:p></div><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">}<o:p class=""></o:p></div><div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""> </o:p></div><div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">I just want to fold the branch. Following Philip’s earlier suggestion, adding a routine CannotBeOrderedLessThanZero (that’s analogous to CannotBeNegativeZero) and making SimplifyFCmpInst use it would be enough to cover the cases of primary interest. Comments?<o:p class=""></o:p></div><div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""> </o:p></div><div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">- Arch</div></div></div></blockquote></div><br class=""></div></body></html>