Add an overlap_op_by_pieces_p target hook for op_by_pieces operations between two areas of memory to generate one offset adjusted operation in the smallest integer mode for the remaining bytes on the last piece operation of a memory region to avoid doing more than one smaller operations.
Pass the RTL information from the previous iteration to m_constfn in op_by_pieces operation so that builtin_memset_[read|gen]_str can generate the new RTL from the previous RTL. The v3 changes: 1. Split changing a while loop in op_by_pieces_d::run to a do-while loop into a separate patch for easier review. 2. Simplify the builtin_memset_read_str change. 3. Document that offset adjusted operation is unaligned. The v2 changes are: 1. Added a target hook, TARGET_OVERLAP_OP_BY_PIECES_P. 2. Added a pointer argument to pieces_addr::adjust to pass the RTL information from the previous iteraton to m_constfn. 3. Updated builtin_memset_read_str and builtin_memset_gen_str to generate the new RTL from the previous RTL info. H.J. Lu (2): op_by_pieces_d::run: Change a while loop to a do-while loop Generate offset adjusted operation for op_by_pieces operations gcc/builtins.c | 36 ++++- gcc/builtins.h | 6 +- gcc/config/i386/i386.c | 3 + gcc/doc/tm.texi | 7 + gcc/doc/tm.texi.in | 2 + gcc/expr.c | 171 ++++++++++++++++----- gcc/expr.h | 10 +- gcc/target.def | 9 ++ gcc/testsuite/g++.dg/pr90773-1.h | 14 ++ gcc/testsuite/g++.dg/pr90773-1a.C | 13 ++ gcc/testsuite/g++.dg/pr90773-1b.C | 5 + gcc/testsuite/g++.dg/pr90773-1c.C | 5 + gcc/testsuite/g++.dg/pr90773-1d.C | 19 +++ gcc/testsuite/gcc.target/i386/pr90773-1.c | 17 ++ gcc/testsuite/gcc.target/i386/pr90773-10.c | 13 ++ gcc/testsuite/gcc.target/i386/pr90773-11.c | 13 ++ gcc/testsuite/gcc.target/i386/pr90773-12.c | 11 ++ gcc/testsuite/gcc.target/i386/pr90773-13.c | 11 ++ gcc/testsuite/gcc.target/i386/pr90773-14.c | 13 ++ gcc/testsuite/gcc.target/i386/pr90773-2.c | 20 +++ gcc/testsuite/gcc.target/i386/pr90773-3.c | 23 +++ gcc/testsuite/gcc.target/i386/pr90773-4.c | 13 ++ gcc/testsuite/gcc.target/i386/pr90773-5.c | 13 ++ gcc/testsuite/gcc.target/i386/pr90773-6.c | 11 ++ gcc/testsuite/gcc.target/i386/pr90773-7.c | 11 ++ gcc/testsuite/gcc.target/i386/pr90773-8.c | 13 ++ gcc/testsuite/gcc.target/i386/pr90773-9.c | 13 ++ 27 files changed, 446 insertions(+), 49 deletions(-) create mode 100644 gcc/testsuite/g++.dg/pr90773-1.h create mode 100644 gcc/testsuite/g++.dg/pr90773-1a.C create mode 100644 gcc/testsuite/g++.dg/pr90773-1b.C create mode 100644 gcc/testsuite/g++.dg/pr90773-1c.C create mode 100644 gcc/testsuite/g++.dg/pr90773-1d.C create mode 100644 gcc/testsuite/gcc.target/i386/pr90773-1.c create mode 100644 gcc/testsuite/gcc.target/i386/pr90773-10.c create mode 100644 gcc/testsuite/gcc.target/i386/pr90773-11.c create mode 100644 gcc/testsuite/gcc.target/i386/pr90773-12.c create mode 100644 gcc/testsuite/gcc.target/i386/pr90773-13.c create mode 100644 gcc/testsuite/gcc.target/i386/pr90773-14.c create mode 100644 gcc/testsuite/gcc.target/i386/pr90773-2.c create mode 100644 gcc/testsuite/gcc.target/i386/pr90773-3.c create mode 100644 gcc/testsuite/gcc.target/i386/pr90773-4.c create mode 100644 gcc/testsuite/gcc.target/i386/pr90773-5.c create mode 100644 gcc/testsuite/gcc.target/i386/pr90773-6.c create mode 100644 gcc/testsuite/gcc.target/i386/pr90773-7.c create mode 100644 gcc/testsuite/gcc.target/i386/pr90773-8.c create mode 100644 gcc/testsuite/gcc.target/i386/pr90773-9.c -- 2.31.1
