On 24/10/16 12:29, Kyrill Tkachov wrote:
Ping.
https://gcc.gnu.org/ml/gcc-patches/2016-10/msg01321.html


I just noticed my original ChangeLog entry was truncated.
It is
2016-10-04  Kyrylo Tkachov  <kyrylo.tkac...@arm.com>

    PR target/77822
    * config/aarch64/aarch64.md (*tb<optab><mode>1): Use
    aarch64_simd_shift_imm_<mode> predicate for operand 1.
    (<optab>, ANY_EXTRACT): Use tighter predicates on operands 2 and 3
    to restrict them to an appropriate range and add FAIL check if the
    region they specify is out of range.  Delete useless constraint
    strings.
    (*<optab><mode>, ANY_EXTRACT): Add appropriate predicates on operands
    2 and 3 to restrict their range and add pattern predicate.

2016-10-04  Kyrylo Tkachov  <kyrylo.tkac...@arm.com>

    PR target/77822
    * g++.dg/torture/pr77822.C: New test.

Kyrill


On 17/10/16 17:15, Kyrill Tkachov wrote:
Hi all,

For the attached testcase the code ends up trying to extract bits outside the 
range of the normal register
widths. The aarch64 patterns for ubfz and tbnz end up accepting such operands 
and emitting invalid assembly
such as 'ubfx x18,x2,192,32'

The solution is to add proper predicates and guards to the operands of the 
zero_extract operations that are going on.
I had a look at all the other patterns in aarch64 that generate/use 
zero_extract and they all have guards on their
operands in one form or another to avoid them accessing an area that is out of 
range.

With this patch the testcase compiles and assembles fine.

Bootstrapped and tested on aarch64-none-linux-gnu.

Ok for trunk?

Thanks,
Kyrill

2016-10-17  Kyrylo Tkachov  <kyrylo.tkac...@arm.com>

    PR target/77822
    * config/aarch64/aarch64.md (*tb<optab><mode>1): Use
    aarch64_simd_shift_imm_<mode> predicate for operand 1.
    (<optab>, ANY_EXTRACT): Use tighter predicates on operands 2 and 3
    to restrict them to an appropriate range and add FAIL check if the
    region they specify is out of range.  Delete useless constraint
    strings.
    (*<optab><mode>, ANY_EXTRACT): Add appropriate predicates on operands
    2 and 3 to restrict their range and add pattern predicate.

2016-10-17  Kyrylo Tkachov  <kyrylo.tkac...@arm.com>

    PR target/77822


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