Hi there,
This patch intends to update thumb1_size_rtx_costs function to correctly
handle those RTXs defined by RTL expansion pass. Thus the GIMPLE
multiplication will be expanded to single mul instruction instead of a bunch
of shift/add/sub instructions which are in fact more expensive.
Tested with GCC regression test on QEMU ARM926, no regression. Is it OK to
trunk and 4.8 branch?
BR,
Terry
gcc/ChangeLog:
2013-07-24 Terry Guo <terry.guo@arm.com>
* config/arm/arm.c (thumb1_size_rtx_costs): Assign proper cost for
shift_add/shift_sub0/shift_sub1 RTXs.
gcc/testsuite/ChangeLog:
2013-07-24 Terry Guo <terry.guo@arm.com>
* gcc.target/arm/thumb1-Os-mult.c: New test case.