diff options
Diffstat (limited to 'lib/Target/PowerPC/README.txt')
| -rw-r--r-- | lib/Target/PowerPC/README.txt | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/lib/Target/PowerPC/README.txt b/lib/Target/PowerPC/README.txt index 3465779..4c80225 100644 --- a/lib/Target/PowerPC/README.txt +++ b/lib/Target/PowerPC/README.txt @@ -37,6 +37,31 @@ _f3: ori r3, r2, 65535 blr +===-------------------------------------------------------------------------=== + +This code: + +unsigned add32carry(unsigned sum, unsigned x) { + unsigned z = sum + x; + if (sum + x < x) + z++; + return z; +} + +Should compile to something like: + + addc r3,r3,r4 + addze r3,r3 + +instead we get: + + add r3, r4, r3 + cmplw cr7, r3, r4 + mfcr r4 ; 1 + rlwinm r4, r4, 29, 31, 31 + add r3, r3, r4 + +Ick. ===-------------------------------------------------------------------------=== |