Re: [PATCH GCC 9/9]Prove no-overflow in computation of LOOP_VINFO_NITERS and improve code generation

2016-10-13 Thread Bin.Cheng
On Mon, Sep 12, 2016 at 8:58 PM, Jeff Law wrote: > On 09/06/2016 12:54 PM, Bin Cheng wrote: >> >> Hi, >> LOOP_VINFO_NITERS is computed as LOOP_VINFO_NITERSM1 + 1, which could >> overflow in loop niters' type. Vectorizer needs to generate more code >> computing vectorized niters

Re: [PATCH GCC 9/9]Prove no-overflow in computation of LOOP_VINFO_NITERS and improve code generation

2016-09-12 Thread Jeff Law
On 09/06/2016 12:54 PM, Bin Cheng wrote: Hi, LOOP_VINFO_NITERS is computed as LOOP_VINFO_NITERSM1 + 1, which could overflow in loop niters' type. Vectorizer needs to generate more code computing vectorized niters if overflow does happen. However, For common loops, there is no overflow

Re: [PATCH GCC 9/9]Prove no-overflow in computation of LOOP_VINFO_NITERS and improve code generation

2016-09-07 Thread kugan
Hi Bin, On 07/09/16 17:52, Bin.Cheng wrote: On Wed, Sep 7, 2016 at 1:10 AM, kugan wrote: Hi Bin, On 07/09/16 04:54, Bin Cheng wrote: Hi, LOOP_VINFO_NITERS is computed as LOOP_VINFO_NITERSM1 + 1, which could overflow in loop niters' type. Vectorizer

Re: [PATCH GCC 9/9]Prove no-overflow in computation of LOOP_VINFO_NITERS and improve code generation

2016-09-07 Thread Bin.Cheng
On Wed, Sep 7, 2016 at 1:10 AM, kugan wrote: > Hi Bin, > > > On 07/09/16 04:54, Bin Cheng wrote: >> >> Hi, >> LOOP_VINFO_NITERS is computed as LOOP_VINFO_NITERSM1 + 1, which could >> overflow in loop niters' type. Vectorizer needs to generate more code >>

Re: [PATCH GCC 9/9]Prove no-overflow in computation of LOOP_VINFO_NITERS and improve code generation

2016-09-06 Thread kugan
Hi Bin, On 07/09/16 04:54, Bin Cheng wrote: Hi, LOOP_VINFO_NITERS is computed as LOOP_VINFO_NITERSM1 + 1, which could overflow in loop niters' type. Vectorizer needs to generate more code computing vectorized niters if overflow does happen. However, For common loops, there is no overflow

[PATCH GCC 9/9]Prove no-overflow in computation of LOOP_VINFO_NITERS and improve code generation

2016-09-06 Thread Bin Cheng
Hi, LOOP_VINFO_NITERS is computed as LOOP_VINFO_NITERSM1 + 1, which could overflow in loop niters' type. Vectorizer needs to generate more code computing vectorized niters if overflow does happen. However, For common loops, there is no overflow actually, this patch tries to prove the