[PATCH] Fix PR80334

[Rainer Orth]

Hi Richard,

> The following patch makes sure to preserve (mis-)alignment of memory
> references when IVOPTs generates TARGET_MEM_REFs for them.
>
> Bootstrapped on x86_64-unknown-linux-gnu, testing in progress.
>
> Richard.
>
> 2017-04-06  Richard Biener  <rguenther@suse.de>
>
> 	PR tree-optimization/80334
> 	* tree-ssa-loop-ivopts.c (rewrite_use_address): Properly
> 	preserve alignment of accesses.
>
> 	* g++.dg/torture/pr80334.C: New testcase.

the new testcase FAILs on 32-bit Solaris/SPARC:

+FAIL: g++.dg/torture/pr80334.C   -O0  (test for excess errors)
+FAIL: g++.dg/torture/pr80334.C   -O1  (test for excess errors)
+FAIL: g++.dg/torture/pr80334.C   -O2  (test for excess errors)
+FAIL: g++.dg/torture/pr80334.C   -O2 -flto  (test for excess errors)
+FAIL: g++.dg/torture/pr80334.C   -O2 -flto -flto-partition=none  (test for exce
ss errors)
+FAIL: g++.dg/torture/pr80334.C   -O3 -fomit-frame-pointer -funroll-loops -fpeel
-loops -ftracer -finline-functions  (test for excess errors)
+FAIL: g++.dg/torture/pr80334.C   -O3 -g  (test for excess errors)
+FAIL: g++.dg/torture/pr80334.C   -Os  (test for excess errors)

Excess errors:
/vol/gcc/src/hg/trunk/local/gcc/testsuite/g++.dg/torture/pr80334.C:11:20: warning: requested alignment 16 is larger than 8 [-Wattributes]

	Rainer

-- 
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Rainer Orth, Center for Biotechnology, Bielefeld University