diff options
| author | amylaar <amylaar@138bc75d-0d04-0410-961f-82ee72b054a4> | 2002-07-16 20:13:35 +0000 |
|---|---|---|
| committer | amylaar <amylaar@138bc75d-0d04-0410-961f-82ee72b054a4> | 2002-07-16 20:13:35 +0000 |
| commit | 14a4ccb4c3fdb0ae4a7126ca818d2aee00cd3b8e (patch) | |
| tree | 0654a0eaf2c78a4f25b1a9a8b0ae119b3f56c05f /gcc | |
| parent | 1c4417b568d45d63789611aa7013788f1bf41582 (diff) | |
| download | gcc-14a4ccb4c3fdb0ae4a7126ca818d2aee00cd3b8e.tar.gz | |
* regrename.c (copy_value): Don't record high part copies.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@55493 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 4 | ||||
| -rw-r--r-- | gcc/regrename.c | 20 |
2 files changed, 24 insertions, 0 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index e36fdc3f021..eecf79785ea 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,7 @@ +Tue Jul 16 19:32:58 2002 J"orn Rennecke <joern.rennecke@superh.com> + + * regrename.c (copy_value): Don't record high part copies. + 2002-07-16 Steve Ellcey <sje@cup.hp.com> * gcc/config/pa/long_double.h (FIXUNS_TRUNCTFDI2_LIBCALL): New define. diff --git a/gcc/regrename.c b/gcc/regrename.c index 532d5753df3..0ceab76c6e2 100644 --- a/gcc/regrename.c +++ b/gcc/regrename.c @@ -1268,6 +1268,26 @@ copy_value (dest, src, vd) if (vd->e[sr].mode == VOIDmode) set_value_regno (sr, vd->e[dr].mode, vd); + /* If we are narrowing the the input to a smaller number of hard regs, + and it is in big endian, we are really extracting a high part. + Since we generally associate a low part of a value with the value itself, + we must not do the same for the high part. + Note we can still get low parts for the same mode combination through + a two-step copy involving differently sized hard regs. + Assume hard regs fr* are 32 bits bits each, while r* are 64 bits each: + (set (reg:DI r0) (reg:DI fr0)) + (set (reg:SI fr2) (reg:SI r0)) + loads the low part of (reg:DI fr0) - i.e. fr1 - into fr2, while: + (set (reg:SI fr2) (reg:SI fr0)) + loads the high part of (reg:DI fr0) into fr2. + + We can't properly represent the latter case in our tables, so don't + record anything then. */ + else if (sn < (unsigned int) HARD_REGNO_NREGS (sr, vd->e[sr].mode) + && (GET_MODE_SIZE (vd->e[sr].mode) > UNITS_PER_WORD + ? WORDS_BIG_ENDIAN : BYTES_BIG_ENDIAN)) + return; + /* If SRC had been assigned a mode narrower than the copy, we can't link DEST into the chain, because not all of the pieces of the copy came from oldest_regno. */ |