https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95863
--- Comment #4 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by H.J. Lu <h...@gcc.gnu.org>: https://gcc.gnu.org/g:4f73bf20d9c0ad1cd143db39d73f70841dcc1471 commit r11-2852-g4f73bf20d9c0ad1cd143db39d73f70841dcc1471 Author: H.J. Lu <hjl.to...@gmail.com> Date: Fri Jun 26 14:56:40 2020 -0700 x86: Change CTZ_DEFINED_VALUE_AT_ZERO to return 0/2 Change CTZ_DEFINED_VALUE_AT_ZERO/CTZ_DEFINED_VALUE_AT_ZERO to return 0/2 to enable table-based clz/ctz optimization: -- Macro: CLZ_DEFINED_VALUE_AT_ZERO (MODE, VALUE) -- Macro: CTZ_DEFINED_VALUE_AT_ZERO (MODE, VALUE) A C expression that indicates whether the architecture defines a value for 'clz' or 'ctz' with a zero operand. A result of '0' indicates the value is undefined. If the value is defined for only the RTL expression, the macro should evaluate to '1'; if the value applies also to the corresponding optab entry (which is normally the case if it expands directly into the corresponding RTL), then the macro should evaluate to '2'. In the cases where the value is defined, VALUE should be set to this value. gcc/ PR target/95863 * config/i386/i386.h (CTZ_DEFINED_VALUE_AT_ZERO): Return 0/2. (CLZ_DEFINED_VALUE_AT_ZERO): Likewise. gcc/testsuite/ PR target/95863 * gcc.target/i386/pr95863-1.c: New test. * gcc.target/i386/pr95863-2.c: Likewise.
