token chains first. For this C function:
int test() {
int i;
for (i = 0; i < 100000; ++i)
foo();
}
Instead of emitting this (condition before call)
.LBB_test_1: ; no_exit
addi r30, r30, 1
lis r2, 1
ori r2, r2, 34464
cmpw cr2, r30, r2
bl L_foo$stub
bne cr2, .LBB_test_1 ; no_exit
Emit this:
.LBB_test_1: ; no_exit
bl L_foo$stub
addi r30, r30, 1
lis r2, 1
ori r2, r2, 34464
cmpw cr0, r30, r2
bne cr0, .LBB_test_1 ; no_exit
Which makes it so we don't have to save/restore cr2 in the prolog/epilog of
the function.
This also makes the code much more similar to what the pattern isel produces.
llvm-svn: 23135
putting it into the constant pool. This allows the isel machinery to
create constants that it will end up deciding are not needed, without them
ending up in the resultant function constant pool.
llvm-svn: 23081
This gets us this for the previous testcase:
_test:
lis r2, 0
ori r3, r2, 65535
blr
Note that we actually write to r3 (the return reg) correctly now :)
llvm-svn: 22933
temporary registers for things that define a register. This allows dag->dag
isel to compile this:
int %test() { ret int 65535 }
into:
_test:
lis r2, 0
ori r2, r2, 65535
blr
Next up, getting CopyFromReg to work, allowing arguments and cross-bb values.
llvm-svn: 22932
