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Subject: [Bug target/45365]  New: X86 FP add and multiply aren't commutative
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According to table 4-7 in chapter 4, Vol 1 of
IA32/Inte64 SDM, x86 FP add and multiply aren't
commutative with Qnan/Snan inputs. But we have

DEF_RTL_EXPR(PLUS, "plus", "ee", RTX_COMM_ARITH)
DEF_RTL_EXPR(MULT, "mult", "ee", RTX_COMM_ARITH)

That impacts x86 FP plus and mult patterns. Should
we introduce a new target option to disable x86
commutative FP plus and mult?


-- 
           Summary: X86 FP add and multiply aren't commutative
           Product: gcc
           Version: 4.5.3
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: hjl dot tools at gmail dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45365