diff options
Diffstat (limited to 'packages/gcc/14.2.0/0014-Add-force_lowpart_subreg.patch')
| -rw-r--r-- | packages/gcc/14.2.0/0014-Add-force_lowpart_subreg.patch | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/packages/gcc/14.2.0/0014-Add-force_lowpart_subreg.patch b/packages/gcc/14.2.0/0014-Add-force_lowpart_subreg.patch new file mode 100644 index 00000000..17fc7b64 --- /dev/null +++ b/packages/gcc/14.2.0/0014-Add-force_lowpart_subreg.patch @@ -0,0 +1,121 @@ +From 2dcdf9d026ed2e881b0bd8b378ed072e410490fe Mon Sep 17 00:00:00 2001 +From: Richard Sandiford <richard.sandiford@arm.com> +Date: Tue, 18 Jun 2024 12:22:31 +0100 +Subject: [PATCH 14/16] Add force_lowpart_subreg + +optabs had a local function called lowpart_subreg_maybe_copy +that is very similar to the lowpart version of force_subreg. +This patch adds a force_lowpart_subreg wrapper around +force_subreg and uses it in optabs.cc. + +The only difference between the old and new functions is that +the old one asserted success while the new one doesn't. +It's common not to assert elsewhere when taking subregs; +normally a null result is enough. + +Later patches will make more use of the new function. + +gcc/ + * explow.h (force_lowpart_subreg): Declare. + * explow.cc (force_lowpart_subreg): New function. + * optabs.cc (lowpart_subreg_maybe_copy): Delete. + (expand_absneg_bit): Use force_lowpart_subreg instead of + lowpart_subreg_maybe_copy. + (expand_copysign_bit): Likewise. + +(cherry picked from commit 5f40d1c0cc6ce91ef28d326b8707b3f05e6f239c) +--- + gcc/explow.cc | 14 ++++++++++++++ + gcc/explow.h | 1 + + gcc/optabs.cc | 24 ++---------------------- + 3 files changed, 17 insertions(+), 22 deletions(-) + +diff --git a/gcc/explow.cc b/gcc/explow.cc +index f6843398c4b..5fdfa81f69b 100644 +--- a/gcc/explow.cc ++++ b/gcc/explow.cc +@@ -760,6 +760,20 @@ force_subreg (machine_mode outermode, rtx op, + return simplify_gen_subreg (outermode, op, innermode, byte); + } + ++/* Try to return an rvalue expression for the OUTERMODE lowpart of OP, ++ which has mode INNERMODE. Allow OP to be forced into a new register ++ if necessary. ++ ++ Return null on failure. */ ++ ++rtx ++force_lowpart_subreg (machine_mode outermode, rtx op, ++ machine_mode innermode) ++{ ++ auto byte = subreg_lowpart_offset (outermode, innermode); ++ return force_subreg (outermode, op, innermode, byte); ++} ++ + /* If X is a memory ref, copy its contents to a new temp reg and return + that reg. Otherwise, return X. */ + +diff --git a/gcc/explow.h b/gcc/explow.h +index cbd1fcb7eb3..dd654649b06 100644 +--- a/gcc/explow.h ++++ b/gcc/explow.h +@@ -43,6 +43,7 @@ extern rtx copy_to_suggested_reg (rtx, rtx, machine_mode); + extern rtx force_reg (machine_mode, rtx); + + extern rtx force_subreg (machine_mode, rtx, machine_mode, poly_uint64); ++extern rtx force_lowpart_subreg (machine_mode, rtx, machine_mode); + + /* Return given rtx, copied into a new temp reg if it was in memory. */ + extern rtx force_not_mem (rtx); +diff --git a/gcc/optabs.cc b/gcc/optabs.cc +index ce91f94ed43..804c0dc73ba 100644 +--- a/gcc/optabs.cc ++++ b/gcc/optabs.cc +@@ -3096,26 +3096,6 @@ expand_ffs (scalar_int_mode mode, rtx op0, rtx target) + return 0; + } + +-/* Extract the OMODE lowpart from VAL, which has IMODE. Under certain +- conditions, VAL may already be a SUBREG against which we cannot generate +- a further SUBREG. In this case, we expect forcing the value into a +- register will work around the situation. */ +- +-static rtx +-lowpart_subreg_maybe_copy (machine_mode omode, rtx val, +- machine_mode imode) +-{ +- rtx ret; +- ret = lowpart_subreg (omode, val, imode); +- if (ret == NULL) +- { +- val = force_reg (imode, val); +- ret = lowpart_subreg (omode, val, imode); +- gcc_assert (ret != NULL); +- } +- return ret; +-} +- + /* Expand a floating point absolute value or negation operation via a + logical operation on the sign bit. */ + +@@ -3204,7 +3184,7 @@ expand_absneg_bit (enum rtx_code code, scalar_float_mode mode, + gen_lowpart (imode, op0), + immed_wide_int_const (mask, imode), + gen_lowpart (imode, target), 1, OPTAB_LIB_WIDEN); +- target = lowpart_subreg_maybe_copy (mode, temp, imode); ++ target = force_lowpart_subreg (mode, temp, imode); + + set_dst_reg_note (get_last_insn (), REG_EQUAL, + gen_rtx_fmt_e (code, mode, copy_rtx (op0)), +@@ -4043,7 +4023,7 @@ expand_copysign_bit (scalar_float_mode mode, rtx op0, rtx op1, rtx target, + + temp = expand_binop (imode, ior_optab, op0, op1, + gen_lowpart (imode, target), 1, OPTAB_LIB_WIDEN); +- target = lowpart_subreg_maybe_copy (mode, temp, imode); ++ target = force_lowpart_subreg (mode, temp, imode); + } + + return target; +-- +2.44.2 + |