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| author | Richard Sandiford <rdsandiford@googlemail.com> | 2011-09-27 17:24:03 +0000 |
|---|---|---|
| committer | Richard Sandiford <rsandifo@gcc.gnu.org> | 2011-09-27 17:24:03 +0000 |
| commit | 8e8af9b74d52e494d10772b03d31d3f3238098dc (patch) | |
| tree | 39f60f475b6218eda95f7ba7195de7c72769f089 /gcc | |
| parent | a744996112debc8f21fc2770dfb001059e01d2e1 (diff) | |
| download | gcc-8e8af9b74d52e494d10772b03d31d3f3238098dc.zip gcc-8e8af9b74d52e494d10772b03d31d3f3238098dc.tar.gz gcc-8e8af9b74d52e494d10772b03d31d3f3238098dc.tar.bz2 | |
fwprop.c (forward_propagate_and_simplify): After checking reg/subreg combinations, check whether the modes are the same.
gcc/
* fwprop.c (forward_propagate_and_simplify): After checking
reg/subreg combinations, check whether the modes are the same.
From-SVN: r179287
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/fwprop.c | 21 |
2 files changed, 17 insertions, 9 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index d05ebc6..ab85f50 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2011-09-27 Richard Sandiford <rdsandiford@googlemail.com> + + * fwprop.c (forward_propagate_and_simplify): After checking + reg/subreg combinations, check whether the modes are the same. + 2011-09-27 Bernd Schmidt <bernds@codesourcery.com> Richard Sandiford <rdsandiford@googlemail.com> diff --git a/gcc/fwprop.c b/gcc/fwprop.c index 236dda2..5368d18 100644 --- a/gcc/fwprop.c +++ b/gcc/fwprop.c @@ -1232,21 +1232,24 @@ forward_propagate_and_simplify (df_ref use, rtx def_insn, rtx def_set) /* If def and use are subreg, check if they match. */ reg = DF_REF_REG (use); - if (GET_CODE (reg) == SUBREG - && GET_CODE (SET_DEST (def_set)) == SUBREG - && (SUBREG_BYTE (SET_DEST (def_set)) != SUBREG_BYTE (reg) - || GET_MODE (SET_DEST (def_set)) != GET_MODE (reg))) - return false; - + if (GET_CODE (reg) == SUBREG && GET_CODE (SET_DEST (def_set)) == SUBREG) + { + if (SUBREG_BYTE (SET_DEST (def_set)) != SUBREG_BYTE (reg)) + return false; + } /* Check if the def had a subreg, but the use has the whole reg. */ - if (REG_P (reg) && GET_CODE (SET_DEST (def_set)) == SUBREG) + else if (REG_P (reg) && GET_CODE (SET_DEST (def_set)) == SUBREG) return false; - /* Check if the use has a subreg, but the def had the whole reg. Unlike the previous case, the optimization is possible and often useful indeed. */ - if (GET_CODE (reg) == SUBREG && REG_P (SET_DEST (def_set))) + else if (GET_CODE (reg) == SUBREG && REG_P (SET_DEST (def_set))) reg = SUBREG_REG (reg); + /* Make sure that we can treat REG as having the same mode as the + source of DEF_SET. */ + if (GET_MODE (SET_DEST (def_set)) != GET_MODE (reg)) + return false; + /* Check if the substitution is valid (last, because it's the most expensive check!). */ src = SET_SRC (def_set); |