| Message ID | AANLkTima5mV3OL=HuY_Sw54NtNU4-0RaY+z6jaNzA0Sc@mail.gmail.com |
|---|---|
| State | New |
| Headers | show |
This final version looks good to me -- and it is more precise. Thanks, David On Fri, Jul 30, 2010 at 1:43 PM, H.J. Lu <hjl.tools@gmail.com> wrote: > On Fri, Jul 30, 2010 at 11:46 AM, H.J. Lu <hjl.tools@gmail.com> wrote: >> On Fri, Jul 30, 2010 at 10:54 AM, Xinliang David Li <davidxl@google.com> wrote: >>> Why is start offset not 1 to begin with? Let's assume it is correct, >>> there are a couple of problems in this patch: >>> >>> 1) when the precision of the HOST_WIDE_INT is the same as the bitsize >>> of the address_mode, max_offset = (HOST_WIDE_INT) 1 << width will >>> produce a negative number >>> 2) last_off should be initialized to 0 to match the original behavior >>> 3) The i&& guard will make sure the loop terminates, but the offset >>> compuation will be wrong -- i<<1 will first overflows to a negative >>> number, then gets truncated to zero, that means when this happens, >>> the last_off will be negative when the loop terminates. >>> >>> David >> >> I don't know exactly what get_address_cost is supposed to do. Here is >> a new patch which avoids overflow and speeds up finding max/min offsets. >> > > > The code is wrong for -m32 on 64bit host. We should start with > the maximum and minimum offsets like: > > width = GET_MODE_BITSIZE (address_mode) - 1; > if (width > (HOST_BITS_PER_WIDE_INT - 1)) > width = HOST_BITS_PER_WIDE_INT - 1; > addr = gen_rtx_fmt_ee (PLUS, address_mode, reg1, NULL_RTX); > > for (i = width; i; i--) > { > off = -((HOST_WIDE_INT) 1 << i); > XEXP (addr, 1) = gen_int_mode (off, address_mode); > if (memory_address_addr_space_p (mem_mode, addr, as)) > break; > } > data->min_offset = off; > > for (i = width; i; i--) > { > off = ((HOST_WIDE_INT) 1 << i) - 1; > XEXP (addr, 1) = gen_int_mode (off, address_mode); > if (memory_address_addr_space_p (mem_mode, addr, as)) > break; > } > data->max_offset = off; > > Here is the updated patch. > > > H.J. > --- >> H.J. >> --- >>> >>> On Fri, Jul 30, 2010 at 10:27 AM, H.J. Lu <hjl.tools@gmail.com> wrote: >>>> On Fri, Jul 30, 2010 at 9:58 AM, Xinliang David Li <davidxl@google.com> wrote: >>>>> There is a problem in this patch -- when i wraps to zero and terminate >>>>> the loop, the maxoffset computed will be zero which is wrong. >>>>> >>>>> My previous patch won't have this problem. >>>> >>>> Your patch changed the start offset. Here is the updated patch. >>>> >>>> >>>> H.J. >>>>> >>>>> David >>>>> >>>>> On Fri, Jul 30, 2010 at 9:49 AM, Xinliang David Li <davidxl@google.com> wrote: >>>>>> This looks fine to me -- Zdenek or other reviewers --- is this one ok? >>>>>> >>>>>> Thanks, >>>>>> >>>>>> David >>>>>> >>>>>> On Fri, Jul 30, 2010 at 8:45 AM, H.J. Lu <hjl.tools@gmail.com> wrote: >>>>>>> On Thu, Jul 29, 2010 at 6:04 PM, H.J. Lu <hjl.tools@gmail.com> wrote: >>>>>>>> It looks strange: >>>>>>>> >>>>>>>> + width = (GET_MODE_BITSIZE (address_mode) < HOST_BITS_PER_WIDE_INT - 1) >>>>>>>> + ? GET_MODE_BITSIZE (address_mode) : HOST_BITS_PER_WIDE_INT - 1; >>>>>>>> addr = gen_rtx_fmt_ee (PLUS, address_mode, reg1, NULL_RTX); >>>>>>>> - for (i = start; i <= 1 << 20; i <<= 1) >>>>>>>> + for (i = 1; i < width; i++) >>>>>>>> { >>>>>>>> - XEXP (addr, 1) = gen_int_mode (i, address_mode); >>>>>>>> + HOST_WIDE_INT offset = (1ll << i); >>>>>>>> + XEXP (addr, 1) = gen_int_mode (offset, address_mode); >>>>>>>> if (!memory_address_addr_space_p (mem_mode, addr, as)) >>>>>>>> break; >>>>>>>> } >>>>>>>> >>>>>>>> HOST_WIDE_INT may be long or long long. "1ll" isn't always correct. >>>>>>>> I think width can be >= 31. Depending on HOST_WIDE_INT, >>>>>>>> >>>>>>>> HOST_WIDE_INT offset = -(1ll << i); >>>>>>>> >>>>>>>> may have different values. The whole function looks odd to me. >>>>>>>> >>>>>>>> >>>>>>> >>>>>>> Here is a different approach to check address overflow. >>>>>>> >>>>>>> >>>>>>> -- >>>>>>> H.J. >>>>>>> -- >>>>>>> 2010-07-29 H.J. Lu <hongjiu.lu@intel.com> >>>>>>> >>>>>>> PR bootstrap/45119 >>>>>>> * tree-ssa-loop-ivopts.c (get_address_cost): Re-apply revision >>>>>>> 162652. Check address overflow. >>>>>>> >>>>>> >>>>> >>>> >>>> >>>> >>>> -- >>>> H.J. >>>> >>> >> >> >> >> -- >> H.J. >> > > > > -- > H.J. >
Compiler bootstrapped and tested with Lu's patch (with one minor change to initialize off variable) (x86-64/linux) -- also checked dump file that offsets are properly computed. Ok for trunk? Thanks, David On Fri, Jul 30, 2010 at 1:43 PM, H.J. Lu <hjl.tools@gmail.com> wrote: > On Fri, Jul 30, 2010 at 11:46 AM, H.J. Lu <hjl.tools@gmail.com> wrote: >> On Fri, Jul 30, 2010 at 10:54 AM, Xinliang David Li <davidxl@google.com> wrote: >>> Why is start offset not 1 to begin with? Let's assume it is correct, >>> there are a couple of problems in this patch: >>> >>> 1) when the precision of the HOST_WIDE_INT is the same as the bitsize >>> of the address_mode, max_offset = (HOST_WIDE_INT) 1 << width will >>> produce a negative number >>> 2) last_off should be initialized to 0 to match the original behavior >>> 3) The i&& guard will make sure the loop terminates, but the offset >>> compuation will be wrong -- i<<1 will first overflows to a negative >>> number, then gets truncated to zero, that means when this happens, >>> the last_off will be negative when the loop terminates. >>> >>> David >> >> I don't know exactly what get_address_cost is supposed to do. Here is >> a new patch which avoids overflow and speeds up finding max/min offsets. >> > > > The code is wrong for -m32 on 64bit host. We should start with > the maximum and minimum offsets like: > > width = GET_MODE_BITSIZE (address_mode) - 1; > if (width > (HOST_BITS_PER_WIDE_INT - 1)) > width = HOST_BITS_PER_WIDE_INT - 1; > addr = gen_rtx_fmt_ee (PLUS, address_mode, reg1, NULL_RTX); > > for (i = width; i; i--) > { > off = -((HOST_WIDE_INT) 1 << i); > XEXP (addr, 1) = gen_int_mode (off, address_mode); > if (memory_address_addr_space_p (mem_mode, addr, as)) > break; > } > data->min_offset = off; > > for (i = width; i; i--) > { > off = ((HOST_WIDE_INT) 1 << i) - 1; > XEXP (addr, 1) = gen_int_mode (off, address_mode); > if (memory_address_addr_space_p (mem_mode, addr, as)) > break; > } > data->max_offset = off; > > Here is the updated patch. > > > H.J. > --- >> H.J. >> --- >>> >>> On Fri, Jul 30, 2010 at 10:27 AM, H.J. Lu <hjl.tools@gmail.com> wrote: >>>> On Fri, Jul 30, 2010 at 9:58 AM, Xinliang David Li <davidxl@google.com> wrote: >>>>> There is a problem in this patch -- when i wraps to zero and terminate >>>>> the loop, the maxoffset computed will be zero which is wrong. >>>>> >>>>> My previous patch won't have this problem. >>>> >>>> Your patch changed the start offset. Here is the updated patch. >>>> >>>> >>>> H.J. >>>>> >>>>> David >>>>> >>>>> On Fri, Jul 30, 2010 at 9:49 AM, Xinliang David Li <davidxl@google.com> wrote: >>>>>> This looks fine to me -- Zdenek or other reviewers --- is this one ok? >>>>>> >>>>>> Thanks, >>>>>> >>>>>> David >>>>>> >>>>>> On Fri, Jul 30, 2010 at 8:45 AM, H.J. Lu <hjl.tools@gmail.com> wrote: >>>>>>> On Thu, Jul 29, 2010 at 6:04 PM, H.J. Lu <hjl.tools@gmail.com> wrote: >>>>>>>> It looks strange: >>>>>>>> >>>>>>>> + width = (GET_MODE_BITSIZE (address_mode) < HOST_BITS_PER_WIDE_INT - 1) >>>>>>>> + ? GET_MODE_BITSIZE (address_mode) : HOST_BITS_PER_WIDE_INT - 1; >>>>>>>> addr = gen_rtx_fmt_ee (PLUS, address_mode, reg1, NULL_RTX); >>>>>>>> - for (i = start; i <= 1 << 20; i <<= 1) >>>>>>>> + for (i = 1; i < width; i++) >>>>>>>> { >>>>>>>> - XEXP (addr, 1) = gen_int_mode (i, address_mode); >>>>>>>> + HOST_WIDE_INT offset = (1ll << i); >>>>>>>> + XEXP (addr, 1) = gen_int_mode (offset, address_mode); >>>>>>>> if (!memory_address_addr_space_p (mem_mode, addr, as)) >>>>>>>> break; >>>>>>>> } >>>>>>>> >>>>>>>> HOST_WIDE_INT may be long or long long. "1ll" isn't always correct. >>>>>>>> I think width can be >= 31. Depending on HOST_WIDE_INT, >>>>>>>> >>>>>>>> HOST_WIDE_INT offset = -(1ll << i); >>>>>>>> >>>>>>>> may have different values. The whole function looks odd to me. >>>>>>>> >>>>>>>> >>>>>>> >>>>>>> Here is a different approach to check address overflow. >>>>>>> >>>>>>> >>>>>>> -- >>>>>>> H.J. >>>>>>> -- >>>>>>> 2010-07-29 H.J. Lu <hongjiu.lu@intel.com> >>>>>>> >>>>>>> PR bootstrap/45119 >>>>>>> * tree-ssa-loop-ivopts.c (get_address_cost): Re-apply revision >>>>>>> 162652. Check address overflow. >>>>>>> >>>>>> >>>>> >>>> >>>> >>>> >>>> -- >>>> H.J. >>>> >>> >> >> >> >> -- >> H.J. >> > > > > -- > H.J. >
Hi, > Compiler bootstrapped and tested with Lu's patch (with one minor > change to initialize off variable) (x86-64/linux) -- also checked dump > file that offsets are properly computed. in case that no offsets are allowed (or more hypotetically, if only offsets of +1 or -1 are allowed), the code below will set min_offset to -2 and max_offset to +2, thus incorrectly extending the range of allowed offsets. Zdenek > reg1 = gen_raw_REG (address_mode, LAST_VIRTUAL_REGISTER + 1); > > + width = GET_MODE_BITSIZE (address_mode) - 1; > + if (width > (HOST_BITS_PER_WIDE_INT - 1)) > + width = HOST_BITS_PER_WIDE_INT - 1; > addr = gen_rtx_fmt_ee (PLUS, address_mode, reg1, NULL_RTX); > - for (i = start; i <= 1 << 20; i <<= 1) > + > + for (i = width; i; i--) > { > - XEXP (addr, 1) = gen_int_mode (i, address_mode); > - if (!memory_address_addr_space_p (mem_mode, addr, as)) > + off = -((HOST_WIDE_INT) 1 << i); > + XEXP (addr, 1) = gen_int_mode (off, address_mode); > + if (memory_address_addr_space_p (mem_mode, addr, as)) > break; > } > - data->max_offset = i == start ? 0 : i >> 1; > - off = data->max_offset; > + data->min_offset = off; > > - for (i = start; i <= 1 << 20; i <<= 1) > + for (i = width; i; i--) > { > - XEXP (addr, 1) = gen_int_mode (-i, address_mode); > - if (!memory_address_addr_space_p (mem_mode, addr, as)) > + off = ((HOST_WIDE_INT) 1 << i) - 1; > + XEXP (addr, 1) = gen_int_mode (off, address_mode); > + if (memory_address_addr_space_p (mem_mode, addr, as)) > break; > } > - data->min_offset = i == start ? 0 : -(i >> 1); > + data->max_offset = off; > > if (dump_file && (dump_flags & TDF_DETAILS)) > { > fprintf (dump_file, "get_address_cost:\n"); > - fprintf (dump_file, " min offset %s %d\n", > + fprintf (dump_file, " min offset %s " HOST_WIDE_INT_PRINT_DEC "\n", > GET_MODE_NAME (mem_mode), > - (int) data->min_offset); > - fprintf (dump_file, " max offset %s %d\n", > + data->min_offset); > + fprintf (dump_file, " max offset %s " HOST_WIDE_INT_PRINT_DEC "\n", > GET_MODE_NAME (mem_mode), > - (int) data->max_offset); > + data->max_offset); > } > > rat = 1;
You are right. The attached is the revised version. Ok this time (after testing is done)? Thanks, David On Mon, Aug 9, 2010 at 12:55 AM, Zdenek Dvorak <rakdver@kam.mff.cuni.cz> wrote: > Hi, > >> Compiler bootstrapped and tested with Lu's patch (with one minor >> change to initialize off variable) (x86-64/linux) -- also checked dump >> file that offsets are properly computed. > > in case that no offsets are allowed (or more hypotetically, if only offsets of > +1 or -1 are allowed), the code below will set min_offset to -2 and max_offset > to +2, thus incorrectly extending the range of allowed offsets. > > Zdenek > >> reg1 = gen_raw_REG (address_mode, LAST_VIRTUAL_REGISTER + 1); >> >> + width = GET_MODE_BITSIZE (address_mode) - 1; >> + if (width > (HOST_BITS_PER_WIDE_INT - 1)) >> + width = HOST_BITS_PER_WIDE_INT - 1; >> addr = gen_rtx_fmt_ee (PLUS, address_mode, reg1, NULL_RTX); >> - for (i = start; i <= 1 << 20; i <<= 1) >> + >> + for (i = width; i; i--) >> { >> - XEXP (addr, 1) = gen_int_mode (i, address_mode); >> - if (!memory_address_addr_space_p (mem_mode, addr, as)) >> + off = -((HOST_WIDE_INT) 1 << i); >> + XEXP (addr, 1) = gen_int_mode (off, address_mode); >> + if (memory_address_addr_space_p (mem_mode, addr, as)) >> break; >> } >> - data->max_offset = i == start ? 0 : i >> 1; >> - off = data->max_offset; >> + data->min_offset = off; >> >> - for (i = start; i <= 1 << 20; i <<= 1) >> + for (i = width; i; i--) >> { >> - XEXP (addr, 1) = gen_int_mode (-i, address_mode); >> - if (!memory_address_addr_space_p (mem_mode, addr, as)) >> + off = ((HOST_WIDE_INT) 1 << i) - 1; >> + XEXP (addr, 1) = gen_int_mode (off, address_mode); >> + if (memory_address_addr_space_p (mem_mode, addr, as)) >> break; >> } >> - data->min_offset = i == start ? 0 : -(i >> 1); >> + data->max_offset = off; >> >> if (dump_file && (dump_flags & TDF_DETAILS)) >> { >> fprintf (dump_file, "get_address_cost:\n"); >> - fprintf (dump_file, " min offset %s %d\n", >> + fprintf (dump_file, " min offset %s " HOST_WIDE_INT_PRINT_DEC "\n", >> GET_MODE_NAME (mem_mode), >> - (int) data->min_offset); >> - fprintf (dump_file, " max offset %s %d\n", >> + data->min_offset); >> + fprintf (dump_file, " max offset %s " HOST_WIDE_INT_PRINT_DEC "\n", >> GET_MODE_NAME (mem_mode), >> - (int) data->max_offset); >> + data->max_offset); >> } >> >> rat = 1; > >
Wrong patch in the last email. Here is the one. David On Mon, Aug 9, 2010 at 3:54 PM, Xinliang David Li <davidxl@google.com> wrote: > You are right. The attached is the revised version. Ok this time > (after testing is done)? > > Thanks, > > David > > On Mon, Aug 9, 2010 at 12:55 AM, Zdenek Dvorak <rakdver@kam.mff.cuni.cz> wrote: >> Hi, >> >>> Compiler bootstrapped and tested with Lu's patch (with one minor >>> change to initialize off variable) (x86-64/linux) -- also checked dump >>> file that offsets are properly computed. >> >> in case that no offsets are allowed (or more hypotetically, if only offsets of >> +1 or -1 are allowed), the code below will set min_offset to -2 and max_offset >> to +2, thus incorrectly extending the range of allowed offsets. >> >> Zdenek >> >>> reg1 = gen_raw_REG (address_mode, LAST_VIRTUAL_REGISTER + 1); >>> >>> + width = GET_MODE_BITSIZE (address_mode) - 1; >>> + if (width > (HOST_BITS_PER_WIDE_INT - 1)) >>> + width = HOST_BITS_PER_WIDE_INT - 1; >>> addr = gen_rtx_fmt_ee (PLUS, address_mode, reg1, NULL_RTX); >>> - for (i = start; i <= 1 << 20; i <<= 1) >>> + >>> + for (i = width; i; i--) >>> { >>> - XEXP (addr, 1) = gen_int_mode (i, address_mode); >>> - if (!memory_address_addr_space_p (mem_mode, addr, as)) >>> + off = -((HOST_WIDE_INT) 1 << i); >>> + XEXP (addr, 1) = gen_int_mode (off, address_mode); >>> + if (memory_address_addr_space_p (mem_mode, addr, as)) >>> break; >>> } >>> - data->max_offset = i == start ? 0 : i >> 1; >>> - off = data->max_offset; >>> + data->min_offset = off; >>> >>> - for (i = start; i <= 1 << 20; i <<= 1) >>> + for (i = width; i; i--) >>> { >>> - XEXP (addr, 1) = gen_int_mode (-i, address_mode); >>> - if (!memory_address_addr_space_p (mem_mode, addr, as)) >>> + off = ((HOST_WIDE_INT) 1 << i) - 1; >>> + XEXP (addr, 1) = gen_int_mode (off, address_mode); >>> + if (memory_address_addr_space_p (mem_mode, addr, as)) >>> break; >>> } >>> - data->min_offset = i == start ? 0 : -(i >> 1); >>> + data->max_offset = off; >>> >>> if (dump_file && (dump_flags & TDF_DETAILS)) >>> { >>> fprintf (dump_file, "get_address_cost:\n"); >>> - fprintf (dump_file, " min offset %s %d\n", >>> + fprintf (dump_file, " min offset %s " HOST_WIDE_INT_PRINT_DEC "\n", >>> GET_MODE_NAME (mem_mode), >>> - (int) data->min_offset); >>> - fprintf (dump_file, " max offset %s %d\n", >>> + data->min_offset); >>> + fprintf (dump_file, " max offset %s " HOST_WIDE_INT_PRINT_DEC "\n", >>> GET_MODE_NAME (mem_mode), >>> - (int) data->max_offset); >>> + data->max_offset); >>> } >>> >>> rat = 1; >> >> >
Hi, > Wrong patch in the last email. Here is the one. > > David > > On Mon, Aug 9, 2010 at 3:54 PM, Xinliang David Li <davidxl@google.com> wrote: > > You are right. The attached is the revised version. Ok this time > > (after testing is done)? OK, Zdenek
On Mon, Aug 9, 2010 at 4:47 PM, Xinliang David Li <davidxl@google.com> wrote: > Wrong patch in the last email. Here is the one. > You changed the code from setting "off" to setting "offset": - data->min_offset = i == start ? 0 : -(i >> 1); + data->max_offset = (i == -1? 0 : off); + offset = data->max_offset; "off" is used later: 3345 if (off_p) 3346 base = gen_rtx_fmt_e (CONST, address_mode, 3347 gen_rtx_fmt_ee 3348 (PLUS, address_mode, base, 3349 gen_int_mode (off, address_mode))) ; 3350 } 3351 else if (off_p) 3352 base = gen_int_mode (off, address_mode); 3353 else You can just add off = 0; before the loop. Then you can use data->min_offset = off; data->max_offset = off; after the loop. It is faster.
On Tue, Aug 10, 2010 at 6:16 AM, H.J. Lu <hjl.tools@gmail.com> wrote: > On Mon, Aug 9, 2010 at 4:47 PM, Xinliang David Li <davidxl@google.com> wrote: >> Wrong patch in the last email. Here is the one. >> > > You changed the code from setting "off" to setting "offset": > > - data->min_offset = i == start ? 0 : -(i >> 1); > + data->max_offset = (i == -1? 0 : off); > + offset = data->max_offset; > > "off" is used later: > > 3345 if (off_p) > 3346 base = gen_rtx_fmt_e (CONST, address_mode, > 3347 gen_rtx_fmt_ee > 3348 (PLUS, address_mode, base, > 3349 gen_int_mode (off, > address_mode))) ; > 3350 } > 3351 else if (off_p) > 3352 base = gen_int_mode (off, address_mode); > 3353 else > > You can just add > > off = 0; > > before the loop. Then you can use > > data->min_offset = off; > data->max_offset = off; > > after the loop. It is faster. > Never mind this comment. But "off" is different from before.
Yes -- fixed the typo. Will retest and then commit. THanks, David On Tue, Aug 10, 2010 at 7:12 AM, H.J. Lu <hjl.tools@gmail.com> wrote: > On Tue, Aug 10, 2010 at 6:16 AM, H.J. Lu <hjl.tools@gmail.com> wrote: >> On Mon, Aug 9, 2010 at 4:47 PM, Xinliang David Li <davidxl@google.com> wrote: >>> Wrong patch in the last email. Here is the one. >>> >> >> You changed the code from setting "off" to setting "offset": >> >> - data->min_offset = i == start ? 0 : -(i >> 1); >> + data->max_offset = (i == -1? 0 : off); >> + offset = data->max_offset; >> >> "off" is used later: >> >> 3345 if (off_p) >> 3346 base = gen_rtx_fmt_e (CONST, address_mode, >> 3347 gen_rtx_fmt_ee >> 3348 (PLUS, address_mode, base, >> 3349 gen_int_mode (off, >> address_mode))) ; >> 3350 } >> 3351 else if (off_p) >> 3352 base = gen_int_mode (off, address_mode); >> 3353 else >> >> You can just add >> >> off = 0; >> >> before the loop. Then you can use >> >> data->min_offset = off; >> data->max_offset = off; >> >> after the loop. It is faster. >> > > Never mind this comment. But "off" is different from before. > > > > -- > H.J. >
On Tue, Aug 10, 2010 at 9:27 AM, Xinliang David Li <davidxl@google.com> wrote: > Yes -- fixed the typo. Will retest and then commit. > Can you post your patch? Thanks. > THanks, > > David > > On Tue, Aug 10, 2010 at 7:12 AM, H.J. Lu <hjl.tools@gmail.com> wrote: >> On Tue, Aug 10, 2010 at 6:16 AM, H.J. Lu <hjl.tools@gmail.com> wrote: >>> On Mon, Aug 9, 2010 at 4:47 PM, Xinliang David Li <davidxl@google.com> wrote: >>>> Wrong patch in the last email. Here is the one. >>>> >>> >>> You changed the code from setting "off" to setting "offset": >>> >>> - data->min_offset = i == start ? 0 : -(i >> 1); >>> + data->max_offset = (i == -1? 0 : off); >>> + offset = data->max_offset; >>> >>> "off" is used later: >>> >>> 3345 if (off_p) >>> 3346 base = gen_rtx_fmt_e (CONST, address_mode, >>> 3347 gen_rtx_fmt_ee >>> 3348 (PLUS, address_mode, base, >>> 3349 gen_int_mode (off, >>> address_mode))) ; >>> 3350 } >>> 3351 else if (off_p) >>> 3352 base = gen_int_mode (off, address_mode); >>> 3353 else >>> >>> You can just add >>> >>> off = 0; >>> >>> before the loop. Then you can use >>> >>> data->min_offset = off; >>> data->max_offset = off; >>> >>> after the loop. It is faster. >>> >> >> Never mind this comment. But "off" is different from before. >> >> >> >> -- >> H.J. >> >
see attached. David On Tue, Aug 10, 2010 at 9:36 AM, H.J. Lu <hjl.tools@gmail.com> wrote: > On Tue, Aug 10, 2010 at 9:27 AM, Xinliang David Li <davidxl@google.com> wrote: >> Yes -- fixed the typo. Will retest and then commit. >> > > Can you post your patch? > > Thanks. > > >> THanks, >> >> David >> >> On Tue, Aug 10, 2010 at 7:12 AM, H.J. Lu <hjl.tools@gmail.com> wrote: >>> On Tue, Aug 10, 2010 at 6:16 AM, H.J. Lu <hjl.tools@gmail.com> wrote: >>>> On Mon, Aug 9, 2010 at 4:47 PM, Xinliang David Li <davidxl@google.com> wrote: >>>>> Wrong patch in the last email. Here is the one. >>>>> >>>> >>>> You changed the code from setting "off" to setting "offset": >>>> >>>> - data->min_offset = i == start ? 0 : -(i >> 1); >>>> + data->max_offset = (i == -1? 0 : off); >>>> + offset = data->max_offset; >>>> >>>> "off" is used later: >>>> >>>> 3345 if (off_p) >>>> 3346 base = gen_rtx_fmt_e (CONST, address_mode, >>>> 3347 gen_rtx_fmt_ee >>>> 3348 (PLUS, address_mode, base, >>>> 3349 gen_int_mode (off, >>>> address_mode))) ; >>>> 3350 } >>>> 3351 else if (off_p) >>>> 3352 base = gen_int_mode (off, address_mode); >>>> 3353 else >>>> >>>> You can just add >>>> >>>> off = 0; >>>> >>>> before the loop. Then you can use >>>> >>>> data->min_offset = off; >>>> data->max_offset = off; >>>> >>>> after the loop. It is faster. >>>> >>> >>> Never mind this comment. But "off" is different from before. >>> >>> >>> >>> -- >>> H.J. >>> >> > > > > -- > H.J. >
On Tue, Aug 10, 2010 at 10:09 AM, Xinliang David Li <davidxl@google.com> wrote: > see attached. > > David > You have + data->max_offset = (i == -1? 0 : off); + off = data->max_offset; if (i == -1) off = 0; data->max_offset; = off; may avoid one memory access.
Ok, if you insist on the perfection :) David On Tue, Aug 10, 2010 at 10:13 AM, H.J. Lu <hjl.tools@gmail.com> wrote: > On Tue, Aug 10, 2010 at 10:09 AM, Xinliang David Li <davidxl@google.com> wrote: >> see attached. >> >> David >> > > You have > > + data->max_offset = (i == -1? 0 : off); > + off = data->max_offset; > > if (i == -1) > off = 0; > data->max_offset; = off; > > may avoid one memory access. > > -- > H.J. >
The committed patch also include a fix to a test case (make it more robust). David On Tue, Aug 10, 2010 at 10:26 AM, Xinliang David Li <davidxl@google.com> wrote: > Ok, if you insist on the perfection :) > > David > > On Tue, Aug 10, 2010 at 10:13 AM, H.J. Lu <hjl.tools@gmail.com> wrote: >> On Tue, Aug 10, 2010 at 10:09 AM, Xinliang David Li <davidxl@google.com> wrote: >>> see attached. >>> >>> David >>> >> >> You have >> >> + data->max_offset = (i == -1? 0 : off); >> + off = data->max_offset; >> >> if (i == -1) >> off = 0; >> data->max_offset; = off; >> >> may avoid one memory access. >> >> -- >> H.J. >> >
diff --git a/gcc/tree-ssa-loop-ivopts.c b/gcc/tree-ssa-loop-ivopts.c index 1d65b4a..b47acc7 100644 --- a/gcc/tree-ssa-loop-ivopts.c +++ b/gcc/tree-ssa-loop-ivopts.c @@ -3241,9 +3241,8 @@ get_address_cost (bool symbol_present, bool var_present, if (!data) { HOST_WIDE_INT i; - HOST_WIDE_INT start = BIGGEST_ALIGNMENT / BITS_PER_UNIT; HOST_WIDE_INT rat, off; - int old_cse_not_expected; + int old_cse_not_expected, width; unsigned sym_p, var_p, off_p, rat_p, add_c; rtx seq, addr, base; rtx reg0, reg1; @@ -3252,33 +3251,38 @@ get_address_cost (bool symbol_present, bool var_present, reg1 = gen_raw_REG (address_mode, LAST_VIRTUAL_REGISTER + 1); + width = GET_MODE_BITSIZE (address_mode) - 1; + if (width > (HOST_BITS_PER_WIDE_INT - 1)) + width = HOST_BITS_PER_WIDE_INT - 1; addr = gen_rtx_fmt_ee (PLUS, address_mode, reg1, NULL_RTX); - for (i = start; i <= 1 << 20; i <<= 1) + + for (i = width; i; i--) { - XEXP (addr, 1) = gen_int_mode (i, address_mode); - if (!memory_address_addr_space_p (mem_mode, addr, as)) + off = -((HOST_WIDE_INT) 1 << i); + XEXP (addr, 1) = gen_int_mode (off, address_mode); + if (memory_address_addr_space_p (mem_mode, addr, as)) break; } - data->max_offset = i == start ? 0 : i >> 1; - off = data->max_offset; + data->min_offset = off; - for (i = start; i <= 1 << 20; i <<= 1) + for (i = width; i; i--) { - XEXP (addr, 1) = gen_int_mode (-i, address_mode); - if (!memory_address_addr_space_p (mem_mode, addr, as)) + off = ((HOST_WIDE_INT) 1 << i) - 1; + XEXP (addr, 1) = gen_int_mode (off, address_mode); + if (memory_address_addr_space_p (mem_mode, addr, as)) break; } - data->min_offset = i == start ? 0 : -(i >> 1); + data->max_offset = off; if (dump_file && (dump_flags & TDF_DETAILS)) { fprintf (dump_file, "get_address_cost:\n"); - fprintf (dump_file, " min offset %s %d\n", + fprintf (dump_file, " min offset %s " HOST_WIDE_INT_PRINT_DEC "\n", GET_MODE_NAME (mem_mode), - (int) data->min_offset); - fprintf (dump_file, " max offset %s %d\n", + data->min_offset); + fprintf (dump_file, " max offset %s " HOST_WIDE_INT_PRINT_DEC "\n", GET_MODE_NAME (mem_mode), - (int) data->max_offset); + data->max_offset); } rat = 1;