https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87370
--- Comment #7 from hjl at gcc dot gnu.org <hjl at gcc dot gnu.org> --- Author: hjl Date: Tue Oct 9 17:17:41 2018 New Revision: 264987 URL: https://gcc.gnu.org/viewcvs?rev=264987&root=gcc&view=rev Log: i386: Use TImode for BLKmode values in 2 integer registers When passing and returning BLKmode values in 2 integer registers, use 1 TImode register instead of 2 DImode registers. Otherwise, V1TImode may be used to move and store such BLKmode values, which prevent RTL optimizations. gcc/ Backport from mainline PR target/87370 * config/i386/i386.c (construct_container): Use TImode for BLKmode values in 2 integer registers. gcc/testsuite/ Backport from mainline PR target/87370 * gcc.target/i386/pr87370.c: New test. Modified: branches/gcc-8-branch/gcc/ChangeLog branches/gcc-8-branch/gcc/config/i386/i386.c branches/gcc-8-branch/gcc/testsuite/ChangeLog