2004-07-23 17:49:16 +00:00
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//===-- LiveInterval.cpp - Live Interval Representation -------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file was developed by the LLVM research group and is distributed under
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// the University of Illinois Open Source License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements the LiveRange and LiveInterval classes. Given some
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// numbering of each the machine instructions an interval [i, j) is said to be a
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// live interval for register v if there is no instruction with number j' > j
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// such that v is live at j' abd there is no instruction with number i' < i such
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// that v is live at i'. In this implementation intervals can have holes,
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// i.e. an interval might look like [1,20), [50,65), [1000,1001). Each
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// individual range is represented as an instance of LiveRange, and the whole
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// interval is represented as an instance of LiveInterval.
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//
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//===----------------------------------------------------------------------===//
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2005-09-21 04:19:09 +00:00
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#include "llvm/CodeGen/LiveInterval.h"
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2004-09-01 22:55:40 +00:00
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#include "llvm/ADT/STLExtras.h"
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2005-05-14 05:34:15 +00:00
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#include "llvm/Target/MRegisterInfo.h"
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2004-09-28 02:38:58 +00:00
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#include <algorithm>
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2004-07-24 02:52:23 +00:00
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#include <iostream>
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#include <map>
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2004-07-23 17:49:16 +00:00
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using namespace llvm;
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// An example for liveAt():
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//
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2004-07-23 18:40:00 +00:00
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// this = [1,4), liveAt(0) will return false. The instruction defining this
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// spans slots [0,3]. The interval belongs to an spilled definition of the
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// variable it represents. This is because slot 1 is used (def slot) and spans
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// up to slot 3 (store slot).
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2004-07-23 17:49:16 +00:00
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//
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2004-07-23 18:13:24 +00:00
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bool LiveInterval::liveAt(unsigned I) const {
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Ranges::const_iterator r = std::upper_bound(ranges.begin(), ranges.end(), I);
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2005-04-21 22:36:52 +00:00
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2004-07-23 17:49:16 +00:00
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if (r == ranges.begin())
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return false;
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--r;
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2004-07-23 18:40:00 +00:00
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return r->contains(I);
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2004-07-23 17:49:16 +00:00
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}
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2004-11-18 03:47:34 +00:00
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// overlaps - Return true if the intersection of the two live intervals is
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// not empty.
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//
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2004-07-23 17:49:16 +00:00
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// An example for overlaps():
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//
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// 0: A = ...
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// 4: B = ...
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// 8: C = A + B ;; last use of A
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//
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// The live intervals should look like:
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//
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// A = [3, 11)
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// B = [7, x)
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// C = [11, y)
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//
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// A->overlaps(C) should return false since we want to be able to join
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// A and C.
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2004-11-18 03:47:34 +00:00
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//
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bool LiveInterval::overlapsFrom(const LiveInterval& other,
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const_iterator StartPos) const {
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const_iterator i = begin();
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const_iterator ie = end();
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const_iterator j = StartPos;
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const_iterator je = other.end();
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assert((StartPos->start <= i->start || StartPos == other.begin()) &&
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2004-11-18 04:02:11 +00:00
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StartPos != other.end() && "Bogus start position hint!");
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This patch makes use of the infrastructure implemented before to safely and
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 07:11:19 +00:00
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2004-07-23 17:49:16 +00:00
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if (i->start < j->start) {
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2004-07-23 18:40:00 +00:00
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i = std::upper_bound(i, ie, j->start);
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2004-07-23 17:49:16 +00:00
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if (i != ranges.begin()) --i;
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2004-07-23 18:40:00 +00:00
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} else if (j->start < i->start) {
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2004-12-04 01:22:09 +00:00
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++StartPos;
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if (StartPos != other.end() && StartPos->start <= i->start) {
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assert(StartPos < other.end() && i < end());
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2004-11-18 04:02:11 +00:00
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j = std::upper_bound(j, je, i->start);
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if (j != other.ranges.begin()) --j;
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}
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2004-07-23 18:40:00 +00:00
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} else {
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return true;
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2004-07-23 17:49:16 +00:00
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}
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2004-11-18 05:28:21 +00:00
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if (j == je) return false;
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while (i != ie) {
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2004-07-23 17:49:16 +00:00
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if (i->start > j->start) {
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2004-07-24 11:44:15 +00:00
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std::swap(i, j);
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std::swap(ie, je);
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2004-07-23 17:49:16 +00:00
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}
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if (i->end > j->start)
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return true;
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++i;
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}
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return false;
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}
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2005-10-20 06:06:30 +00:00
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/// NontrivialOverlap - Check to see if the two live ranges specified by i and j
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/// overlap. If so, check to see if they have value numbers that are not
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/// iIdx/jIdx respectively. If both conditions are true, return true.
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2005-10-20 07:39:25 +00:00
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static inline bool NontrivialOverlap(const LiveRange &I, const LiveRange &J,
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2005-10-20 06:06:30 +00:00
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unsigned iIdx, unsigned jIdx) {
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2005-10-20 07:39:25 +00:00
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if (I.start == J.start) {
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2005-10-20 06:06:30 +00:00
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// If this is not the allowed value merge, we cannot join.
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2005-10-20 07:39:25 +00:00
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if (I.ValId != iIdx || J.ValId != jIdx)
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2005-10-20 06:06:30 +00:00
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return true;
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2005-10-20 07:39:25 +00:00
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} else if (I.start < J.start) {
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2005-10-20 16:56:40 +00:00
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if (I.end > J.start && (I.ValId != iIdx || J.ValId != jIdx)) {
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2005-10-20 06:06:30 +00:00
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return true;
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}
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} else {
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2005-10-20 16:56:40 +00:00
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if (J.end > I.start && (I.ValId != iIdx || J.ValId != jIdx))
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2005-10-20 06:06:30 +00:00
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return true;
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}
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return false;
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}
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2004-07-24 02:52:23 +00:00
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/// joinable - Two intervals are joinable if the either don't overlap at all
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/// or if the destination of the copy is a single assignment value, and it
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/// only overlaps with one value in the source interval.
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bool LiveInterval::joinable(const LiveInterval &other, unsigned CopyIdx) const {
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This patch makes use of the infrastructure implemented before to safely and
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 07:11:19 +00:00
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const LiveRange *SourceLR = other.getLiveRangeContaining(CopyIdx-1);
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const LiveRange *DestLR = getLiveRangeContaining(CopyIdx);
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assert(SourceLR && DestLR && "Not joining due to a copy?");
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unsigned OtherValIdx = SourceLR->ValId;
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unsigned ThisValIdx = DestLR->ValId;
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Ranges::const_iterator i = ranges.begin();
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Ranges::const_iterator ie = ranges.end();
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Ranges::const_iterator j = other.ranges.begin();
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Ranges::const_iterator je = other.ranges.end();
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if (i->start < j->start) {
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i = std::upper_bound(i, ie, j->start);
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if (i != ranges.begin()) --i;
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} else if (j->start < i->start) {
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j = std::upper_bound(j, je, i->start);
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if (j != other.ranges.begin()) --j;
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}
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while (i != ie && j != je) {
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2005-10-20 07:39:25 +00:00
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if (NontrivialOverlap(*i, *j, ThisValIdx, OtherValIdx))
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2005-10-20 06:06:30 +00:00
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return false;
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This patch makes use of the infrastructure implemented before to safely and
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 07:11:19 +00:00
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if (i->end < j->end)
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++i;
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else
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++j;
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}
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2004-07-25 07:47:25 +00:00
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return true;
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2004-07-24 02:52:23 +00:00
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}
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2005-10-20 07:39:25 +00:00
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/// getOverlapingRanges - Given another live interval which is defined as a
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/// copy from this one, return a list of all of the live ranges where the
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/// two overlap and have different value numbers.
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|
|
void LiveInterval::getOverlapingRanges(const LiveInterval &other,
|
|
|
|
unsigned CopyIdx,
|
|
|
|
std::vector<LiveRange*> &Ranges) {
|
2005-10-21 06:41:30 +00:00
|
|
|
const LiveRange *SourceLR = getLiveRangeContaining(CopyIdx-1);
|
|
|
|
const LiveRange *DestLR = other.getLiveRangeContaining(CopyIdx);
|
2005-10-20 07:39:25 +00:00
|
|
|
assert(SourceLR && DestLR && "Not joining due to a copy?");
|
|
|
|
unsigned OtherValIdx = SourceLR->ValId;
|
|
|
|
unsigned ThisValIdx = DestLR->ValId;
|
|
|
|
|
|
|
|
Ranges::iterator i = ranges.begin();
|
|
|
|
Ranges::iterator ie = ranges.end();
|
|
|
|
Ranges::const_iterator j = other.ranges.begin();
|
|
|
|
Ranges::const_iterator je = other.ranges.end();
|
|
|
|
|
|
|
|
if (i->start < j->start) {
|
|
|
|
i = std::upper_bound(i, ie, j->start);
|
|
|
|
if (i != ranges.begin()) --i;
|
|
|
|
} else if (j->start < i->start) {
|
|
|
|
j = std::upper_bound(j, je, i->start);
|
|
|
|
if (j != other.ranges.begin()) --j;
|
|
|
|
}
|
|
|
|
|
|
|
|
while (i != ie && j != je) {
|
|
|
|
if (NontrivialOverlap(*i, *j, ThisValIdx, OtherValIdx))
|
|
|
|
Ranges.push_back(&*i);
|
|
|
|
|
|
|
|
if (i->end < j->end)
|
|
|
|
++i;
|
|
|
|
else
|
|
|
|
++j;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
|
2004-07-24 02:52:23 +00:00
|
|
|
|
2004-07-23 19:38:44 +00:00
|
|
|
/// extendIntervalEndTo - This method is used when we want to extend the range
|
|
|
|
/// specified by I to end at the specified endpoint. To do this, we should
|
|
|
|
/// merge and eliminate all ranges that this will overlap with. The iterator is
|
|
|
|
/// not invalidated.
|
|
|
|
void LiveInterval::extendIntervalEndTo(Ranges::iterator I, unsigned NewEnd) {
|
|
|
|
assert(I != ranges.end() && "Not a valid interval!");
|
2004-07-24 02:52:23 +00:00
|
|
|
unsigned ValId = I->ValId;
|
2004-07-23 19:38:44 +00:00
|
|
|
|
|
|
|
// Search for the first interval that we can't merge with.
|
|
|
|
Ranges::iterator MergeTo = next(I);
|
2004-07-24 02:52:23 +00:00
|
|
|
for (; MergeTo != ranges.end() && NewEnd >= MergeTo->end; ++MergeTo) {
|
|
|
|
assert(MergeTo->ValId == ValId && "Cannot merge with differing values!");
|
|
|
|
}
|
2004-07-23 19:38:44 +00:00
|
|
|
|
|
|
|
// If NewEnd was in the middle of an interval, make sure to get its endpoint.
|
|
|
|
I->end = std::max(NewEnd, prior(MergeTo)->end);
|
|
|
|
|
2005-10-20 07:39:25 +00:00
|
|
|
// Erase any dead ranges.
|
2004-07-23 19:38:44 +00:00
|
|
|
ranges.erase(next(I), MergeTo);
|
2005-10-20 07:39:25 +00:00
|
|
|
|
|
|
|
// If the newly formed range now touches the range after it and if they have
|
|
|
|
// the same value number, merge the two ranges into one range.
|
2005-10-20 22:50:10 +00:00
|
|
|
Ranges::iterator Next = next(I);
|
2005-10-21 06:41:30 +00:00
|
|
|
if (Next != ranges.end() && Next->start <= I->end && Next->ValId == ValId) {
|
2005-10-20 22:50:10 +00:00
|
|
|
I->end = Next->end;
|
|
|
|
ranges.erase(Next);
|
2005-10-20 07:39:25 +00:00
|
|
|
}
|
2004-07-23 17:49:16 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
|
2004-07-23 19:38:44 +00:00
|
|
|
/// extendIntervalStartTo - This method is used when we want to extend the range
|
|
|
|
/// specified by I to start at the specified endpoint. To do this, we should
|
|
|
|
/// merge and eliminate all ranges that this will overlap with.
|
2005-04-21 22:36:52 +00:00
|
|
|
LiveInterval::Ranges::iterator
|
2004-07-23 19:38:44 +00:00
|
|
|
LiveInterval::extendIntervalStartTo(Ranges::iterator I, unsigned NewStart) {
|
|
|
|
assert(I != ranges.end() && "Not a valid interval!");
|
2004-07-24 02:52:23 +00:00
|
|
|
unsigned ValId = I->ValId;
|
2004-07-23 19:38:44 +00:00
|
|
|
|
|
|
|
// Search for the first interval that we can't merge with.
|
|
|
|
Ranges::iterator MergeTo = I;
|
|
|
|
do {
|
|
|
|
if (MergeTo == ranges.begin()) {
|
|
|
|
I->start = NewStart;
|
2004-07-24 02:52:23 +00:00
|
|
|
ranges.erase(MergeTo, I);
|
2004-07-23 19:38:44 +00:00
|
|
|
return I;
|
|
|
|
}
|
2004-07-24 02:52:23 +00:00
|
|
|
assert(MergeTo->ValId == ValId && "Cannot merge with differing values!");
|
2004-07-23 19:38:44 +00:00
|
|
|
--MergeTo;
|
|
|
|
} while (NewStart <= MergeTo->start);
|
|
|
|
|
|
|
|
// If we start in the middle of another interval, just delete a range and
|
|
|
|
// extend that interval.
|
2004-07-24 02:52:23 +00:00
|
|
|
if (MergeTo->end >= NewStart && MergeTo->ValId == ValId) {
|
2004-07-23 19:38:44 +00:00
|
|
|
MergeTo->end = I->end;
|
|
|
|
} else {
|
|
|
|
// Otherwise, extend the interval right after.
|
|
|
|
++MergeTo;
|
|
|
|
MergeTo->start = NewStart;
|
|
|
|
MergeTo->end = I->end;
|
2004-07-23 17:49:16 +00:00
|
|
|
}
|
2004-07-23 19:38:44 +00:00
|
|
|
|
|
|
|
ranges.erase(next(MergeTo), next(I));
|
|
|
|
return MergeTo;
|
2004-07-23 17:49:16 +00:00
|
|
|
}
|
|
|
|
|
2006-08-25 23:41:24 +00:00
|
|
|
LiveInterval::iterator
|
|
|
|
LiveInterval::addRangeFrom(LiveRange LR, iterator From) {
|
2004-07-23 19:38:44 +00:00
|
|
|
unsigned Start = LR.start, End = LR.end;
|
2006-08-25 23:41:24 +00:00
|
|
|
iterator it = std::upper_bound(From, ranges.end(), Start);
|
2004-07-23 19:38:44 +00:00
|
|
|
|
|
|
|
// If the inserted interval starts in the middle or right at the end of
|
|
|
|
// another interval, just extend that interval to contain the range of LR.
|
|
|
|
if (it != ranges.begin()) {
|
2006-08-25 23:41:24 +00:00
|
|
|
iterator B = prior(it);
|
2004-07-24 02:52:23 +00:00
|
|
|
if (LR.ValId == B->ValId) {
|
|
|
|
if (B->start <= Start && B->end >= Start) {
|
|
|
|
extendIntervalEndTo(B, End);
|
|
|
|
return B;
|
|
|
|
}
|
|
|
|
} else {
|
|
|
|
// Check to make sure that we are not overlapping two live ranges with
|
|
|
|
// different ValId's.
|
|
|
|
assert(B->end <= Start &&
|
2004-11-16 06:52:35 +00:00
|
|
|
"Cannot overlap two LiveRanges with differing ValID's"
|
|
|
|
" (did you def the same reg twice in a MachineInstr?)");
|
2004-07-23 19:38:44 +00:00
|
|
|
}
|
2004-07-23 17:49:16 +00:00
|
|
|
}
|
2004-07-23 19:38:44 +00:00
|
|
|
|
|
|
|
// Otherwise, if this range ends in the middle of, or right next to, another
|
|
|
|
// interval, merge it into that interval.
|
2004-07-24 02:52:23 +00:00
|
|
|
if (it != ranges.end())
|
|
|
|
if (LR.ValId == it->ValId) {
|
|
|
|
if (it->start <= End) {
|
|
|
|
it = extendIntervalStartTo(it, Start);
|
|
|
|
|
|
|
|
// If LR is a complete superset of an interval, we may need to grow its
|
|
|
|
// endpoint as well.
|
|
|
|
if (End > it->end)
|
|
|
|
extendIntervalEndTo(it, End);
|
|
|
|
return it;
|
|
|
|
}
|
|
|
|
} else {
|
|
|
|
// Check to make sure that we are not overlapping two live ranges with
|
|
|
|
// different ValId's.
|
|
|
|
assert(it->start >= End &&
|
|
|
|
"Cannot overlap two LiveRanges with differing ValID's");
|
|
|
|
}
|
2004-07-23 19:38:44 +00:00
|
|
|
|
|
|
|
// Otherwise, this is just a new range that doesn't interact with anything.
|
|
|
|
// Insert it.
|
|
|
|
return ranges.insert(it, LR);
|
2004-07-23 17:49:16 +00:00
|
|
|
}
|
|
|
|
|
2004-07-24 02:52:23 +00:00
|
|
|
|
|
|
|
/// removeRange - Remove the specified range from this interval. Note that
|
|
|
|
/// the range must already be in this interval in its entirety.
|
|
|
|
void LiveInterval::removeRange(unsigned Start, unsigned End) {
|
|
|
|
// Find the LiveRange containing this span.
|
|
|
|
Ranges::iterator I = std::upper_bound(ranges.begin(), ranges.end(), Start);
|
|
|
|
assert(I != ranges.begin() && "Range is not in interval!");
|
|
|
|
--I;
|
|
|
|
assert(I->contains(Start) && I->contains(End-1) &&
|
|
|
|
"Range is not entirely in interval!");
|
|
|
|
|
|
|
|
// If the span we are removing is at the start of the LiveRange, adjust it.
|
|
|
|
if (I->start == Start) {
|
|
|
|
if (I->end == End)
|
|
|
|
ranges.erase(I); // Removed the whole LiveRange.
|
|
|
|
else
|
|
|
|
I->start = End;
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
// Otherwise if the span we are removing is at the end of the LiveRange,
|
|
|
|
// adjust the other way.
|
|
|
|
if (I->end == End) {
|
2004-07-25 05:43:53 +00:00
|
|
|
I->end = Start;
|
2004-07-24 02:52:23 +00:00
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
// Otherwise, we are splitting the LiveRange into two pieces.
|
|
|
|
unsigned OldEnd = I->end;
|
|
|
|
I->end = Start; // Trim the old interval.
|
|
|
|
|
|
|
|
// Insert the new one.
|
|
|
|
ranges.insert(next(I), LiveRange(End, OldEnd, I->ValId));
|
|
|
|
}
|
|
|
|
|
|
|
|
/// getLiveRangeContaining - Return the live range that contains the
|
|
|
|
/// specified index, or null if there is none.
|
2006-08-24 22:43:55 +00:00
|
|
|
LiveInterval::const_iterator
|
|
|
|
LiveInterval::FindLiveRangeContaining(unsigned Idx) const {
|
|
|
|
const_iterator It = std::upper_bound(begin(), end(), Idx);
|
2004-07-24 02:52:23 +00:00
|
|
|
if (It != ranges.begin()) {
|
2006-08-24 22:43:55 +00:00
|
|
|
--It;
|
|
|
|
if (It->contains(Idx))
|
|
|
|
return It;
|
2004-07-24 02:52:23 +00:00
|
|
|
}
|
|
|
|
|
2006-08-24 22:43:55 +00:00
|
|
|
return end();
|
2004-07-24 02:52:23 +00:00
|
|
|
}
|
|
|
|
|
2006-08-24 22:43:55 +00:00
|
|
|
LiveInterval::iterator
|
|
|
|
LiveInterval::FindLiveRangeContaining(unsigned Idx) {
|
|
|
|
iterator It = std::upper_bound(begin(), end(), Idx);
|
|
|
|
if (It != ranges.begin()) {
|
|
|
|
--It;
|
|
|
|
if (It->contains(Idx))
|
|
|
|
return It;
|
|
|
|
}
|
|
|
|
|
|
|
|
return end();
|
|
|
|
}
|
2004-07-24 02:52:23 +00:00
|
|
|
|
|
|
|
/// join - Join two live intervals (this, and other) together. This operation
|
|
|
|
/// is the result of a copy instruction in the source program, that occurs at
|
|
|
|
/// index 'CopyIdx' that copies from 'Other' to 'this'.
|
|
|
|
void LiveInterval::join(LiveInterval &Other, unsigned CopyIdx) {
|
2004-07-25 06:23:01 +00:00
|
|
|
const LiveRange *SourceLR = Other.getLiveRangeContaining(CopyIdx-1);
|
|
|
|
const LiveRange *DestLR = getLiveRangeContaining(CopyIdx);
|
2004-07-24 02:52:23 +00:00
|
|
|
assert(SourceLR && DestLR && "Not joining due to a copy?");
|
|
|
|
unsigned MergedSrcValIdx = SourceLR->ValId;
|
|
|
|
unsigned MergedDstValIdx = DestLR->ValId;
|
2004-07-23 17:49:16 +00:00
|
|
|
|
2004-07-24 03:41:50 +00:00
|
|
|
// Try to do the least amount of work possible. In particular, if there are
|
|
|
|
// more liverange chunks in the other set than there are in the 'this' set,
|
|
|
|
// swap sets to merge the fewest chunks in possible.
|
|
|
|
if (Other.ranges.size() > ranges.size()) {
|
|
|
|
std::swap(MergedSrcValIdx, MergedDstValIdx);
|
|
|
|
std::swap(ranges, Other.ranges);
|
|
|
|
std::swap(NumValues, Other.NumValues);
|
2006-08-24 22:43:55 +00:00
|
|
|
std::swap(InstDefiningValue, Other.InstDefiningValue);
|
2004-07-24 03:41:50 +00:00
|
|
|
}
|
|
|
|
|
2004-07-23 19:38:44 +00:00
|
|
|
// Join the ranges of other into the ranges of this interval.
|
2004-07-24 02:52:23 +00:00
|
|
|
std::map<unsigned, unsigned> Dst2SrcIdxMap;
|
2006-08-25 23:41:24 +00:00
|
|
|
iterator InsertPos = begin();
|
|
|
|
for (iterator I = Other.begin(), E = Other.end(); I != E; ++I) {
|
2004-07-24 02:52:23 +00:00
|
|
|
// Map the ValId in the other live range to the current live range.
|
|
|
|
if (I->ValId == MergedSrcValIdx)
|
|
|
|
I->ValId = MergedDstValIdx;
|
|
|
|
else {
|
|
|
|
unsigned &NV = Dst2SrcIdxMap[I->ValId];
|
2006-08-22 18:19:46 +00:00
|
|
|
if (NV == 0) NV = getNextValue(Other.getInstForValNum(I->ValId));
|
2004-07-24 02:52:23 +00:00
|
|
|
I->ValId = NV;
|
|
|
|
}
|
2004-07-23 19:38:44 +00:00
|
|
|
|
2004-07-24 02:52:23 +00:00
|
|
|
InsertPos = addRangeFrom(*I, InsertPos);
|
|
|
|
}
|
2006-08-24 22:43:55 +00:00
|
|
|
|
|
|
|
// Update the value number information for the value number defined by the
|
|
|
|
// copy. The copy is about to be removed, so ensure that the value is defined
|
|
|
|
// by whatever the other value is defined by.
|
|
|
|
if (InstDefiningValue[MergedDstValIdx] == CopyIdx) {
|
|
|
|
InstDefiningValue[MergedDstValIdx] =
|
|
|
|
Other.InstDefiningValue[MergedSrcValIdx];
|
|
|
|
}
|
|
|
|
|
2004-07-24 02:52:23 +00:00
|
|
|
weight += Other.weight;
|
2004-07-23 17:49:16 +00:00
|
|
|
}
|
|
|
|
|
2006-08-25 23:41:24 +00:00
|
|
|
/// MergeInClobberRanges - For any live ranges that are not defined in the
|
|
|
|
/// current interval, but are defined in the Clobbers interval, mark them
|
|
|
|
/// used with an unknown definition value.
|
|
|
|
void LiveInterval::MergeInClobberRanges(const LiveInterval &Clobbers) {
|
|
|
|
if (Clobbers.begin() == Clobbers.end()) return;
|
|
|
|
|
|
|
|
// Find a value # to use for the clobber ranges. If there is already a value#
|
|
|
|
// for unknown values, use it.
|
|
|
|
// FIXME: Use a single sentinal number for these!
|
|
|
|
unsigned ClobberValNo = getNextValue(~0U);
|
|
|
|
|
|
|
|
iterator IP = begin();
|
|
|
|
for (const_iterator I = Clobbers.begin(), E = Clobbers.end(); I != E; ++I) {
|
|
|
|
unsigned Start = I->start, End = I->end;
|
|
|
|
IP = std::upper_bound(IP, end(), Start);
|
|
|
|
|
|
|
|
// If the start of this range overlaps with an existing liverange, trim it.
|
|
|
|
if (IP != begin() && IP[-1].end > Start) {
|
|
|
|
Start = IP[-1].end;
|
|
|
|
// Trimmed away the whole range?
|
|
|
|
if (Start >= End) continue;
|
|
|
|
}
|
|
|
|
// If the end of this range overlaps with an existing liverange, trim it.
|
|
|
|
if (IP != end() && End > IP->start) {
|
|
|
|
End = IP->start;
|
|
|
|
// If this trimmed away the whole range, ignore it.
|
|
|
|
if (Start == End) continue;
|
|
|
|
}
|
|
|
|
|
|
|
|
// Insert the clobber interval.
|
|
|
|
IP = addRangeFrom(LiveRange(Start, End, ClobberValNo), IP);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2006-08-24 22:43:55 +00:00
|
|
|
/// MergeValueNumberInto - This method is called when two value nubmers
|
|
|
|
/// are found to be equivalent. This eliminates V1, replacing all
|
|
|
|
/// LiveRanges with the V1 value number with the V2 value number. This can
|
|
|
|
/// cause merging of V1/V2 values numbers and compaction of the value space.
|
|
|
|
void LiveInterval::MergeValueNumberInto(unsigned V1, unsigned V2) {
|
|
|
|
assert(V1 != V2 && "Identical value#'s are always equivalent!");
|
|
|
|
|
|
|
|
// This code actually merges the (numerically) larger value number into the
|
|
|
|
// smaller value number, which is likely to allow us to compactify the value
|
|
|
|
// space. The only thing we have to be careful of is to preserve the
|
|
|
|
// instruction that defines the result value.
|
|
|
|
|
|
|
|
// Make sure V2 is smaller than V1.
|
|
|
|
if (V1 < V2) {
|
|
|
|
setInstDefiningValNum(V1, getInstForValNum(V2));
|
|
|
|
std::swap(V1, V2);
|
|
|
|
}
|
|
|
|
|
|
|
|
// Merge V1 live ranges into V2.
|
|
|
|
for (iterator I = begin(); I != end(); ) {
|
|
|
|
iterator LR = I++;
|
|
|
|
if (LR->ValId != V1) continue; // Not a V1 LiveRange.
|
|
|
|
|
|
|
|
// Okay, we found a V1 live range. If it had a previous, touching, V2 live
|
|
|
|
// range, extend it.
|
|
|
|
if (LR != begin()) {
|
|
|
|
iterator Prev = LR-1;
|
|
|
|
if (Prev->ValId == V2 && Prev->end == LR->start) {
|
|
|
|
Prev->end = LR->end;
|
|
|
|
|
|
|
|
// Erase this live-range.
|
|
|
|
ranges.erase(LR);
|
|
|
|
I = Prev+1;
|
|
|
|
LR = Prev;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
// Okay, now we have a V1 or V2 live range that is maximally merged forward.
|
|
|
|
// Ensure that it is a V2 live-range.
|
|
|
|
LR->ValId = V2;
|
|
|
|
|
|
|
|
// If we can merge it into later V2 live ranges, do so now. We ignore any
|
|
|
|
// following V1 live ranges, as they will be merged in subsequent iterations
|
|
|
|
// of the loop.
|
|
|
|
if (I != end()) {
|
|
|
|
if (I->start == LR->end && I->ValId == V2) {
|
|
|
|
LR->end = I->end;
|
|
|
|
ranges.erase(I);
|
|
|
|
I = LR+1;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
2006-08-24 23:22:59 +00:00
|
|
|
|
|
|
|
// Now that V1 is dead, remove it. If it is the largest value number, just
|
|
|
|
// nuke it (and any other deleted values neighboring it), otherwise mark it as
|
|
|
|
// ~1U so it can be nuked later.
|
|
|
|
if (V1 == NumValues-1) {
|
|
|
|
do {
|
|
|
|
InstDefiningValue.pop_back();
|
|
|
|
--NumValues;
|
|
|
|
} while (InstDefiningValue.back() == ~1U);
|
|
|
|
} else {
|
|
|
|
InstDefiningValue[V1] = ~1U;
|
|
|
|
}
|
2006-08-24 22:43:55 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
|
2004-07-23 17:49:16 +00:00
|
|
|
std::ostream& llvm::operator<<(std::ostream& os, const LiveRange &LR) {
|
2004-07-24 02:52:23 +00:00
|
|
|
return os << '[' << LR.start << ',' << LR.end << ':' << LR.ValId << ")";
|
|
|
|
}
|
|
|
|
|
|
|
|
void LiveRange::dump() const {
|
|
|
|
std::cerr << *this << "\n";
|
2004-07-23 17:49:16 +00:00
|
|
|
}
|
|
|
|
|
2005-05-14 05:34:15 +00:00
|
|
|
void LiveInterval::print(std::ostream &OS, const MRegisterInfo *MRI) const {
|
|
|
|
if (MRI && MRegisterInfo::isPhysicalRegister(reg))
|
|
|
|
OS << MRI->getName(reg);
|
|
|
|
else
|
|
|
|
OS << "%reg" << reg;
|
|
|
|
|
|
|
|
OS << ',' << weight;
|
|
|
|
|
|
|
|
if (empty())
|
|
|
|
OS << "EMPTY";
|
|
|
|
else {
|
|
|
|
OS << " = ";
|
|
|
|
for (LiveInterval::Ranges::const_iterator I = ranges.begin(),
|
|
|
|
E = ranges.end(); I != E; ++I)
|
|
|
|
OS << *I;
|
|
|
|
}
|
2006-08-22 18:19:46 +00:00
|
|
|
|
|
|
|
// Print value number info.
|
|
|
|
if (NumValues) {
|
|
|
|
OS << " ";
|
|
|
|
for (unsigned i = 0; i != NumValues; ++i) {
|
|
|
|
if (i) OS << " ";
|
|
|
|
OS << i << "@";
|
|
|
|
if (InstDefiningValue[i] == ~0U) {
|
|
|
|
OS << "?";
|
|
|
|
} else {
|
|
|
|
OS << InstDefiningValue[i];
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
2004-07-23 17:49:16 +00:00
|
|
|
}
|
2004-07-24 02:52:23 +00:00
|
|
|
|
|
|
|
void LiveInterval::dump() const {
|
|
|
|
std::cerr << *this << "\n";
|
|
|
|
}
|