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| author | Richard Sandiford <richard.sandiford@linaro.org> | 2017-09-04 10:48:40 +0000 |
|---|---|---|
| committer | Richard Sandiford <rsandifo@gcc.gnu.org> | 2017-09-04 10:48:40 +0000 |
| commit | 3d09ba95c150d9676f9a2585fb61315e86fa644a (patch) | |
| tree | 6c37f118811f8cff123ef56870a20145fd74b472 /gcc/expmed.c | |
| parent | d8c40eff56f69877b33c697ded756d50fde90c27 (diff) | |
| download | gcc-3d09ba95c150d9676f9a2585fb61315e86fa644a.tar.gz | |
Add subreg_memory_offset helper functions
This patch adds routines for converting a SUBREG_BYTE offset into a
memory address offset. The two only differ for paradoxical subregs,
where SUBREG_BYTE is always 0 but the memory address offset can be
negative.
2017-09-04 Richard Sandiford <richard.sandiford@linaro.org>
Alan Hayward <alan.hayward@arm.com>
David Sherwood <david.sherwood@arm.com>
gcc/
* rtl.h (subreg_memory_offset): Declare.
* emit-rtl.c (subreg_memory_offset): New function.
* expmed.c (store_bit_field_1): Use it.
* expr.c (undefined_operand_subword_p): Likewise.
* simplify-rtx.c (simplify_subreg): Likewise.
Co-Authored-By: Alan Hayward <alan.hayward@arm.com>
Co-Authored-By: David Sherwood <david.sherwood@arm.com>
From-SVN: r251644
Diffstat (limited to 'gcc/expmed.c')
| -rw-r--r-- | gcc/expmed.c | 24 |
1 files changed, 1 insertions, 23 deletions
diff --git a/gcc/expmed.c b/gcc/expmed.c index ff9eb5b2c71..f82bfc75627 100644 --- a/gcc/expmed.c +++ b/gcc/expmed.c @@ -727,29 +727,7 @@ store_bit_field_1 (rtx str_rtx, unsigned HOST_WIDE_INT bitsize, while (GET_CODE (op0) == SUBREG) { - /* The following line once was done only if WORDS_BIG_ENDIAN, - but I think that is a mistake. WORDS_BIG_ENDIAN is - meaningful at a much higher level; when structures are copied - between memory and regs, the higher-numbered regs - always get higher addresses. */ - int inner_mode_size = GET_MODE_SIZE (GET_MODE (SUBREG_REG (op0))); - int outer_mode_size = GET_MODE_SIZE (GET_MODE (op0)); - int byte_offset = 0; - - /* Paradoxical subregs need special handling on big-endian machines. */ - if (paradoxical_subreg_p (op0)) - { - int difference = inner_mode_size - outer_mode_size; - - if (WORDS_BIG_ENDIAN) - byte_offset += (difference / UNITS_PER_WORD) * UNITS_PER_WORD; - if (BYTES_BIG_ENDIAN) - byte_offset += difference % UNITS_PER_WORD; - } - else - byte_offset = SUBREG_BYTE (op0); - - bitnum += byte_offset * BITS_PER_UNIT; + bitnum += subreg_memory_offset (op0) * BITS_PER_UNIT; op0 = SUBREG_REG (op0); } |