| Andrew Lenharth | a5cc38b | 2006-06-04 00:25:51 +0000 | [diff] [blame] | 1 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
| 2 | Fix Ordered/Unordered FP stuff |
| 3 | |
| 4 | |
| 5 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
| 6 | improve bytezap opertunities |
| 7 | ulong %foo(ulong %y) { |
| 8 | entry: |
| 9 | %tmp = and ulong %y, 65535 |
| 10 | %tmp2 = shr ulong %tmp, ubyte 3 |
| 11 | ret ulong %tmp2 |
| 12 | } |
| 13 | |
| 14 | |
| 15 | compiles to a 3 instruction sequence without instcombine |
| 16 | zapnot $16,3,$0 |
| 17 | srl $0,3,$0 |
| 18 | ret $31,($26),1 |
| 19 | |
| 20 | After instcombine you get |
| 21 | ulong %foo(ulong %y) { |
| 22 | entry: |
| 23 | %tmp = shr ulong %y, ubyte 3 ; <ulong> [#uses=1] |
| 24 | %tmp2 = and ulong %tmp, 8191 ; <ulong> [#uses=1] |
| 25 | ret ulong %tmp2 |
| 26 | } |
| 27 | |
| 28 | which compiles to |
| 29 | lda $0,8191($31) |
| 30 | srl $16,3,$1 |
| 31 | and $1,$0,$0 |
| 32 | ret $31,($26),1 |
| 33 | |