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Age	Commit message (Collapse)	Author
2004-07-25	Fix the sense of joinable	Chris Lattner
	git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15196 91177308-0d34-0410-b5e6-96231b3b80d8
2004-07-25	This patch makes use of the infrastructure implemented before to safely and	Chris Lattner
	aggressively coallesce live ranges even if they overlap. Consider this LLVM code for example: int %test(int %X) { %Y = mul int %X, 1 ;; Codegens to Y = X %Z = add int %X, %Y ret int %Z } The mul is just there to get a copy into the code stream. This produces this machine code: (0x869e5a8, LLVM BB @0x869b9a0): %reg1024 = mov <fi#-2>, 1, %NOREG, 0 ;; "X" %reg1025 = mov %reg1024 ;; "Y" (subsumed by X) %reg1026 = add %reg1024, %reg1025 %EAX = mov %reg1026 ret Note that the life times of reg1024 and reg1025 overlap, even though they contain the same value. This results in this machine code: test: mov %EAX, DWORD PTR [%ESP + 4] mov %ECX, %EAX add %EAX, %ECX ret Another, worse case involves loops and PHI nodes. Consider this trivial loop: testcase: int %test2(int %X) { entry: br label %Loop Loop: %Y = phi int [%X, %entry], [%Z, %Loop] %Z = add int %Y, 1 %cond = seteq int %Z, 100 br bool %cond, label %Out, label %Loop Out: ret int %Z } Because of interactions between the PHI elimination pass and the register allocator, this got compiled to this code: test2: mov %ECX, DWORD PTR [%ESP + 4] .LBBtest2_1: * mov %EAX, %ECX inc %EAX cmp %EAX, 100 * mov %ECX, %EAX jne .LBBtest2_1 ret Or on powerpc, this code: _test2: mflr r0 stw r0, 8(r1) stwu r1, -60(r1) .LBB_test2_1: addi r2, r3, 1 cmpwi cr0, r2, 100 * or r3, r2, r2 bne cr0, .LBB_test2_1 * or r3, r2, r2 lwz r0, 68(r1) mtlr r0 addi r1, r1, 60 blr 0 With this improvement in place, we now generate this code for these two testcases, which is what we want: test: mov %EAX, DWORD PTR [%ESP + 4] add %EAX, %EAX ret test2: mov %EAX, DWORD PTR [%ESP + 4] .LBBtest2_1: inc %EAX cmp %EAX, 100 jne .LBBtest2_1 # Loop ret Or on PPC: _test2: mflr r0 stw r0, 8(r1) stwu r1, -60(r1) .LBB_test2_1: addi r3, r3, 1 cmpwi cr0, r3, 100 bne cr0, .LBB_test2_1 lwz r0, 68(r1) mtlr r0 addi r1, r1, 60 blr 0 Static numbers for spill code loads/stores/reg-reg copies (smaller is better): em3d: before: 47/25/26 after: 44/22/24 164.gzip: before: 433/245/310 after: 403/231/278 175.vpr: before: 3721/2189/1581 after: 4144/2081/1423 176.gcc: before: 26195/8866/9235 after: 25942/8082/8275 186.crafty: before: 4295/2587/3079 after: 4119/2519/2916 252.eon: before: 12754/7585/5803 after: 12508/7425/5643 256.bzip2: before: 463/226/315 after: 482:241/309 Runtime perf number samples on X86: gzip: before: 41.09 after: 39.86 bzip2: runtime: before: 56.71s after: 57.07s gcc: before: 6.16 after: 6.12 eon: before: 2.03s after: 2.00s git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15194 91177308-0d34-0410-b5e6-96231b3b80d8
2004-07-25	Make a method const, no functionality changes	Chris Lattner
	git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15193 91177308-0d34-0410-b5e6-96231b3b80d8
2004-07-25	Fix a bug in the range remover	Chris Lattner
	git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15188 91177308-0d34-0410-b5e6-96231b3b80d8
2004-07-24	Change std::map<unsigned, LiveInterval*> into a std::map<unsigned,	Alkis Evlogimenos
	LiveInterval>. This saves some space and removes the pointer indirection caused by following the pointer. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15167 91177308-0d34-0410-b5e6-96231b3b80d8
2004-07-24	In the joiner, merge the small interval into the large interval. This restores	Chris Lattner
	us back to taking about 10.5s on gcc, instead of taking 15.6s! The net result is that my big patches have hand no significant effect on compile time or code quality. heh. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15156 91177308-0d34-0410-b5e6-96231b3b80d8
2004-07-24	Little stuff:	Chris Lattner
	* Fix comment typeo * add dump() methods * add a few new methods like getLiveRangeContaining, removeRange & joinable (which is currently the same as overlaps) * Remove the unused operator== Bigger change: * In LiveInterval, instead of using a boolean isDefinedOnce to keep track of if there are > 1 definitions in a particular interval, keep a counter, NumValues to keep track of exactly how many there are. * In LiveRange, add a new ValId element to indicate which of the numbered values each LiveRange belongs to. We now no longer merge LiveRanges if they are of differing value ID's even if they are neighbors. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15152 91177308-0d34-0410-b5e6-96231b3b80d8
2004-07-23	Change addRange and join to be a little bit smarter. In particular, we don't	Chris Lattner
	want to insert a new range into the middle of the vector, then delete ranges one at a time next to the inserted one as they are merged. Instead, if the inserted interval overlaps, just start merging. The only time we insert into the middle of the vector is when we don't overlap at all. Also delete blocks of live ranges if we overlap with many of them. This patch speeds up joining by .7 seconds on a large testcase, but more importantly gets all of the range adding code into addRangeFrom. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15141 91177308-0d34-0410-b5e6-96231b3b80d8
2004-07-23	Search by the start point, not by the whole interval. This saves some	Chris Lattner
	comparisons, reducing linscan by another .1 seconds :) git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15139 91177308-0d34-0410-b5e6-96231b3b80d8
2004-07-23	Instead of searching for a live interval pair, search for a location. This ↵	Chris Lattner
	gives a very modest speedup of .3 seconds compiling 176.gcc (out of 20s). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15136 91177308-0d34-0410-b5e6-96231b3b80d8
2004-07-23	Pull the LiveRange and LiveInterval classes out of LiveIntervals.h (which	Chris Lattner
	will soon be renamed) into their own file. The new file should not emit DEBUG output or have other side effects. The LiveInterval class also now doesn't know whether its working on registers or some other thing. In the future we will want to use the LiveInterval class and friends to do stack packing. In addition to a code simplification, this will allow us to do it more easily. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15134 91177308-0d34-0410-b5e6-96231b3b80d8