[Bug target/80307] New: [7 regression] MUL generated for small multiplier cores

[thopre01 at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80307

            Bug ID: 80307
           Summary: [7 regression] MUL generated for small multiplier
                    cores
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: normal
          Priority: P3
         Component: target
          Assignee: thopre01 at gcc dot gnu.org
          Reporter: thopre01 at gcc dot gnu.org
  Target Milestone: ---
            Target: arm-none-eabi

Hi,

The following test have regressed between GCC 6 and GCC7:

gcc.target/arm/small-multiply-m0-1.s
gcc.target/arm/small-multiply-m0plus-1.s
gcc.target/arm/small-multiply-m1-1.s

This is due to r241965 which led to the use of the new cost model. The speed
cost of small multiply was only written for the old cost model.