[llvm-bugs] [Bug 37751] New: [X86] CVTTPD2DQ/CVTTPS2DQ intrinsics must not map to ISD::FP_TO_SINT etc.

via llvm-bugs llvm-bugs at lists.llvm.org
Fri Jun 8 09:38:51 PDT 2018


https://bugs.llvm.org/show_bug.cgi?id=37751

            Bug ID: 37751
           Summary: [X86] CVTTPD2DQ/CVTTPS2DQ intrinsics must not map to
                    ISD::FP_TO_SINT etc.
           Product: libraries
           Version: trunk
          Hardware: PC
                OS: Windows NT
            Status: NEW
          Severity: enhancement
          Priority: P
         Component: Backend: X86
          Assignee: unassignedbugs at nondot.org
          Reporter: llvm-dev at redking.me.uk
                CC: andrea.dibiagio at gmail.com, craig.topper at gmail.com,
                    efriedma at codeaurora.org, filcab at gmail.com,
                    greg.bedwell at sony.com, llvm-bugs at lists.llvm.org,
                    spatel+llvm at rotateright.com

Now that we have FP_TO_*INT combines in DAGCombine (rL330437 for rounding
etc.), we can no longer safely map x86 f2i intrinsics to generic types:

X86_INTRINSIC_DATA(avx_cvtt_ps2dq_256,INTR_TYPE_1OP, ISD::FP_TO_SINT, 0)

as this will lose the intrinsics' special case handling for out of range
values.

All these values need mapping to the X86ISD equivalents (CVTTP2SI/CVTTP2UI)
instead and suitable constant folding support adding so we don't lose any
functionality.

-- 
You are receiving this mail because:
You are on the CC list for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-bugs/attachments/20180608/d9dbeac0/attachment.html>


More information about the llvm-bugs mailing list