This patch makes LRA well with some exceptions (e.g. MI thunk generation due to pretending reload_completed).
gcc/ChangeLog: * config/xtensa/constraints.md (R, T, U): Change define_constraint to define_memory_constraint. * config/xtensa/xtensa.cc (xtensa_legitimate_constant_p): Add short-circuit path for integer load instructions when lra_in_progress. * config/xtensa/xtensa.md (movsf): Use can_create_pseudo_p() rather reload_in_progress and reload_completed. --- gcc/config/xtensa/constraints.md | 26 ++++++++------------------ gcc/config/xtensa/xtensa.cc | 4 ++++ gcc/config/xtensa/xtensa.md | 2 +- 3 files changed, 13 insertions(+), 19 deletions(-) diff --git a/gcc/config/xtensa/constraints.md b/gcc/config/xtensa/constraints.md index 53e4d0d8dd1..9b31e162941 100644 --- a/gcc/config/xtensa/constraints.md +++ b/gcc/config/xtensa/constraints.md @@ -123,29 +123,19 @@ (and (match_code "const_int") (match_test "! xtensa_split1_finished_p ()")))) -;; Memory constraints. Do not use define_memory_constraint here. Doing so -;; causes reload to force some constants into the constant pool, but since -;; the Xtensa constant pool can only be accessed with L32R instructions, it -;; is always better to just copy a constant into a register. Instead, use -;; regular constraints but add a check to allow pseudos during reload. +;; Memory constraints. -(define_constraint "R" +(define_memory_constraint "R" "Memory that can be accessed with a 4-bit unsigned offset from a register." - (ior (and (match_code "mem") - (match_test "smalloffset_mem_p (op)")) - (and (match_code "reg") - (match_test "reload_in_progress - && REGNO (op) >= FIRST_PSEUDO_REGISTER")))) + (and (match_code "mem") + (match_test "smalloffset_mem_p (op)"))) -(define_constraint "T" +(define_memory_constraint "T" "Memory in a literal pool (addressable with an L32R instruction)." (and (match_code "mem") (match_test "!TARGET_CONST16 && constantpool_mem_p (op)"))) -(define_constraint "U" +(define_memory_constraint "U" "Memory that is not in a literal pool." - (ior (and (match_code "mem") - (match_test "! constantpool_mem_p (op)")) - (and (match_code "reg") - (match_test "reload_in_progress - && REGNO (op) >= FIRST_PSEUDO_REGISTER")))) + (and (match_code "mem") + (match_test "! constantpool_mem_p (op)"))) diff --git a/gcc/config/xtensa/xtensa.cc b/gcc/config/xtensa/xtensa.cc index 7287aa7a258..a500dc2a06e 100644 --- a/gcc/config/xtensa/xtensa.cc +++ b/gcc/config/xtensa/xtensa.cc @@ -4872,6 +4872,10 @@ xtensa_trampoline_init (rtx m_tramp, tree fndecl, rtx chain) static bool xtensa_legitimate_constant_p (machine_mode mode ATTRIBUTE_UNUSED, rtx x) { + if (lra_in_progress && CONST_INT_P (x)) + return TARGET_AUTO_LITPOOLS || TARGET_CONST16 + || xtensa_simm12b (INTVAL (x)); + return !xtensa_tls_referenced_p (x); } diff --git a/gcc/config/xtensa/xtensa.md b/gcc/config/xtensa/xtensa.md index 3521fa33b47..195515d9427 100644 --- a/gcc/config/xtensa/xtensa.md +++ b/gcc/config/xtensa/xtensa.md @@ -1268,7 +1268,7 @@ if ((!register_operand (operands[0], SFmode) && !register_operand (operands[1], SFmode)) || (FP_REG_P (xt_true_regnum (operands[0])) - && !(reload_in_progress | reload_completed) + && can_create_pseudo_p () && (constantpool_mem_p (operands[1]) || CONSTANT_P (operands[1])))) operands[1] = force_reg (SFmode, operands[1]); -- 2.30.2