diff options
Diffstat (limited to 'gcc/caller-save.c')
| -rw-r--r-- | gcc/caller-save.c | 27 |
1 files changed, 20 insertions, 7 deletions
diff --git a/gcc/caller-save.c b/gcc/caller-save.c index 87a13dc0fad..920bafd241b 100644 --- a/gcc/caller-save.c +++ b/gcc/caller-save.c @@ -115,6 +115,9 @@ init_caller_save () rtx address; int i, j; enum machine_mode mode; + rtx savepat, restpat; + rtx test_reg, test_mem; + rtx saveinsn, restinsn; /* First find all the registers that we need to deal with and all the modes that they can have. If we can't find a mode to use, @@ -179,7 +182,17 @@ init_caller_save () address = addr_reg; /* Next we try to form an insn to save and restore the register. We - see if such an insn is recognized and meets its constraints. */ + see if such an insn is recognized and meets its constraints. + + To avoid lots of unnecessary RTL allocation, we construct all the RTL + once, then modify the memory and register operands in-place. */ + + test_reg = gen_rtx_REG (VOIDmode, 0); + test_mem = gen_rtx_MEM (VOIDmode, address); + savepat = gen_rtx_SET (VOIDmode, test_mem, test_reg); + restpat = gen_rtx_SET (VOIDmode, test_reg, test_mem); + saveinsn = emit_insn (savepat); + restinsn = emit_insn (restpat); start_sequence (); @@ -187,14 +200,14 @@ init_caller_save () for (mode = 0 ; mode < MAX_MACHINE_MODE; mode++) if (HARD_REGNO_MODE_OK (i, mode)) { - rtx mem = gen_rtx_MEM (mode, address); - rtx reg = gen_rtx_REG (mode, i); - rtx savepat = gen_rtx_SET (VOIDmode, mem, reg); - rtx restpat = gen_rtx_SET (VOIDmode, reg, mem); - rtx saveinsn = emit_insn (savepat); - rtx restinsn = emit_insn (restpat); int ok; + /* Update the register number and modes of the register + and memory operand. */ + REGNO (test_reg) = i; + PUT_MODE (test_reg, mode); + PUT_MODE (test_mem, mode); + reg_save_code[i][mode] = recog_memoized (saveinsn); reg_restore_code[i][mode] = recog_memoized (restinsn); |