16 Commits

Author SHA1 Message Date
Alkis Evlogimenos
43b587d94d Add coalescing to register allocator. A hint is added to each interval
which denotes the register we would like to be assigned to (virtual or
physical). In register allocation, if this hint exists and we can map
it to a physical register (it is either a physical register or it is a
virtual register that already got assigned to a physical one) we use
that register if it is available instead of a random one in the free
pool.

llvm-svn: 10634
2003-12-28 17:58:18 +00:00
Alkis Evlogimenos
eeea81483f Do a separate pass to compute spill weights because doing it inline
with live intervals was missing registers that were used before they
were defined (in the arbitrary order live intervals numbers
instructions).

llvm-svn: 10603
2003-12-24 15:44:53 +00:00
Alkis Evlogimenos
3ec903474f Fix crash when compiling twolf.
llvm-svn: 10584
2003-12-22 13:54:29 +00:00
Alkis Evlogimenos
2665d9c6f9 Change weight into a float so that we can take into account the
nesting level when computing it. Right now the allocator uses:

    w = sum_over_defs_uses( 10 ^ nesting level );

llvm-svn: 10569
2003-12-21 20:19:10 +00:00
Alkis Evlogimenos
c09b77ea35 Add support for inactive intervals. This effectively reuses registers
for live ranges that fall into assigned registers' holes.

llvm-svn: 10566
2003-12-21 05:43:40 +00:00
Alkis Evlogimenos
7139090fd2 Remove TwoAddressInstruction from the public headers and add an ID
instead, since this pass doesn't expose any state to its users.

llvm-svn: 10520
2003-12-18 22:40:24 +00:00
Alkis Evlogimenos
e5e2bd6777 Modify linear scan register allocator to use the two-address
instruction pass. This also fixes all remaining bugs for this new
allocator to pass all tests under test/Programs.

llvm-svn: 10515
2003-12-18 13:15:02 +00:00
Alkis Evlogimenos
15b8036b29 When a variable is killed and redifined in a basic block only one
killing instruction is tracked. This causes the LiveIntervals to
create bogus intervals. The workaound is to add a range to the
interval from the redefinition to the end of the basic block.

llvm-svn: 10510
2003-12-18 08:53:43 +00:00
Alkis Evlogimenos
40874c708f Handle multiple virtual register definitions gracefully.
Move some of the longer LiveIntervals::Interval method out of the
header and add debug information to them. Fix bug and simplify range
merging code.

llvm-svn: 10509
2003-12-18 08:48:48 +00:00
Alkis Evlogimenos
8870674da7 Change preserve all claim to just preserve live variables and phielimination.
llvm-svn: 10469
2003-12-15 04:55:38 +00:00
Alkis Evlogimenos
aaba4639f8 Change interface of MachineOperand as follows:
a) remove opIsUse(), opIsDefOnly(), opIsDefAndUse()
    b) add isUse(), isDef()
    c) rename opHiBits32() to isHiBits32(),
              opLoBits32() to isLoBits32(),
              opHiBits64() to isHiBits64(),
              opLoBits64() to isLoBits64().

This results to much more readable code, for example compare
"op.opIsDef() || op.opIsDefAndUse()" to "op.isDef()" a pattern used
very often in the code.

llvm-svn: 10461
2003-12-14 13:24:17 +00:00
Alkis Evlogimenos
7dbdf3839c Ignore non-allocatable physical registers in live interval analysis.
llvm-svn: 10449
2003-12-13 11:11:02 +00:00
Alkis Evlogimenos
06f379a278 Handle explicit physical register defs.
llvm-svn: 10445
2003-12-13 05:26:39 +00:00
Alkis Evlogimenos
2de099e54f Move operator<<(std::ostream&, const LiveInterval&) out of the header file.
llvm-svn: 10290
2003-12-05 10:38:28 +00:00
Alkis Evlogimenos
ed28ca93ef Sort live intervals by increasing start point.
llvm-svn: 10289
2003-12-05 10:32:01 +00:00
Alkis Evlogimenos
0e9ded74c0 Merging the linear scan register allocator in trunk. It currently passes most tests under test/Programs/SingleSource/Benchmarks/Shootout so development will continue on trunk. The allocator is not enabled by default. You will need to pass -regallo=linearscan to lli or llc to use it.
llvm-svn: 10103
2003-11-20 03:32:25 +00:00