a predecessor appearing more than once in the operand list was counted as
multiple predecessor; priority1 should be updated during scheduling;
CycleBound was updated after the node is inserted into priority queue; one
of the tie breaking condition was flipped.
- Take into consideration of two address opcodes. If a predecessor is a def&use
operand, it should have a higher priority.
- Scheduler should also favor floaters, i.e. nodes that do not have real
predecessors such as MOV32ri.
- The scheduling fixes / tweaks fixed bug 478:
.text
.align 4
.globl _f
_f:
movl 4(%esp), %eax
movl 8(%esp), %ecx
movl %eax, %edx
imull %ecx, %edx
imull %eax, %eax
imull %ecx, %ecx
addl %eax, %ecx
leal (%ecx,%edx,2), %eax
ret
It is also a slight performance win (1% - 3%) for most tests.
llvm-svn: 26470