diff options
Diffstat (limited to 'gcc/function.c')
| -rw-r--r-- | gcc/function.c | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/gcc/function.c b/gcc/function.c index ffee598..5f2dd48 100644 --- a/gcc/function.c +++ b/gcc/function.c @@ -2591,7 +2591,21 @@ assign_parm_setup_block (struct assign_parm_data_all *all, #endif ) { - rtx reg = gen_rtx_REG (mode, REGNO (entry_parm)); + rtx reg; + + /* We are really truncating a word_mode value containing + SIZE bytes into a value of mode MODE. If such an + operation requires no actual instructions, we can refer + to the value directly in mode MODE, otherwise we must + start with the register in word_mode and explicitly + convert it. */ + if (TRULY_NOOP_TRUNCATION (size * BITS_PER_UNIT, BITS_PER_WORD)) + reg = gen_rtx_REG (mode, REGNO (entry_parm)); + else + { + reg = gen_rtx_REG (word_mode, REGNO (entry_parm)); + reg = convert_to_mode (mode, copy_to_reg (reg), 1); + } emit_move_insn (change_address (mem, mode, 0), reg); } |