[Bug tree-optimization/54295] [4.7 Regression] Widening multiply-accumulate operation uses wrong value extension

[rearnsha at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54295

--- Comment #6 from Richard Earnshaw <rearnsha at gcc dot gnu.org> 2012-09-07 
10:37:12 UTC ---
Author: rearnsha
Date: Fri Sep  7 10:37:08 2012
New Revision: 191066

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=191066
Log:
    PR tree-ssa/54295
    * tree-ssa-math-opts.c (widening_mult_conversion_strippable_p):
    Sign-extension of a zero-extended value can be simplified to
    just zero-extension.

testsuite:
    * gcc.target/arm/pr50318-1.c: Scan for smlal.
    * gcc.target/arm/smlaltb-1.c: XFAIL test.
    * gcc.target/arm/smlaltt-1.c: Likewise.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gcc.target/arm/pr50318-1.c
    trunk/gcc/testsuite/gcc.target/arm/smlaltb-1.c
    trunk/gcc/testsuite/gcc.target/arm/smlaltt-1.c
    trunk/gcc/tree-ssa-math-opts.c