Re: [RFC] Handle LHS zero_extracts in DSE

2018-12-13 Thread Jeff Law
On 12/7/18 8:57 AM, Andreas Krebbel wrote: > Hi, > > debugging a problem with an older GCC (4.6). I've seen RTXs using > ZERO_EXTRACT LHS operands on MEMs as in: > > (insn 7 6 0 (set (zero_extract:DI (mem/s/c:QI (plus:DI (reg/f:DI 39 > virtual-stack-vars) > (const_int -5 [0xff

[RFC] Handle LHS zero_extracts in DSE

2018-12-07 Thread Andreas Krebbel
Hi, debugging a problem with an older GCC (4.6). I've seen RTXs using ZERO_EXTRACT LHS operands on MEMs as in: (insn 7 6 0 (set (zero_extract:DI (mem/s/c:QI (plus:DI (reg/f:DI 39 virtual-stack-vars) (const_int -5 [0xfffb])) [0+0 S1 A8]) (const_int 24