Commit Graph

2150 Commits

Author SHA1 Message Date
Chris Lattner 6bf2cd5735 Add support for alloca, implementing ctor-list-opt.ll:CTOR6
llvm-svn: 23452
2005-09-26 17:07:09 +00:00
Chris Lattner 46d9ff081d Add a debug printout, fix a crash on kc++
llvm-svn: 23450
2005-09-26 07:34:35 +00:00
Chris Lattner 46af55e0e4 Implement loads/stores through GEP's of globals. This implements
ctor-list-opt.ll:CTOR5.

llvm-svn: 23449
2005-09-26 06:52:44 +00:00
Chris Lattner 61ff32cd70 Replace TraverseGEPInitializer with ConstantFoldLoadThroughGEPConstantExpr
llvm-svn: 23447
2005-09-26 05:34:07 +00:00
Chris Lattner 02ae21e1e0 Eliminate GetGEPGlobalInitializer in favor of the more powerful
ConstantFoldLoadThroughGEPConstantExpr function in the utils lib.

llvm-svn: 23446
2005-09-26 05:28:52 +00:00
Chris Lattner 0b011ec8e2 Factor the GetGEPGlobalInitializer out of this pass and into Transforms/Utils
as ConstantFoldLoadThroughGEPConstantExpr.

llvm-svn: 23445
2005-09-26 05:28:06 +00:00
Chris Lattner c13c7b9376 Move the ConstantFoldLoadThroughGEPConstantExpr function out of the InstCombine
pass.

llvm-svn: 23444
2005-09-26 05:27:10 +00:00
Chris Lattner b009663e27 add a comment
llvm-svn: 23442
2005-09-26 05:16:34 +00:00
Chris Lattner 4b05c322d5 Add support for getelementptr, load, and correctly reject volatile stores.
llvm-svn: 23441
2005-09-26 05:15:37 +00:00
Chris Lattner 3e9ea5ffec Add support for br/brcond/switch and phi
llvm-svn: 23439
2005-09-26 04:57:38 +00:00
Chris Lattner 99e23fa74c Add a simple interpreter to this code, allowing us to statically evaluate
global ctors that are simple enough.  This implements ctor-list-opt.ll:CTOR2.

llvm-svn: 23437
2005-09-26 04:44:35 +00:00
Chris Lattner 696beefabb factor some code into a InstallGlobalCtors method, add comments. No functionality change.
llvm-svn: 23435
2005-09-26 02:31:18 +00:00
Chris Lattner 838bdc1836 Make the global opt optimizer work on modules with a null terminator, by
accepting the null even with a non-65535 init prio

llvm-svn: 23434
2005-09-26 02:19:27 +00:00
Chris Lattner 41b6a5a693 Factor this code out into a few methods.
Implement the start of global ctor optimization.  It is currently smart
enough to remove the global ctor for cases like this:

struct foo {
  foo() {}
} x;

... saving a bit of startup time for the program.

llvm-svn: 23433
2005-09-26 01:43:45 +00:00
Chris Lattner f487768062 Fix some logic I broke that caused a regression on
SimplifyLibCalls/2005-05-20-sprintf-crash.ll

llvm-svn: 23430
2005-09-25 07:06:48 +00:00
Chris Lattner 0b3557f54a Move MaskedValueIsZero up.
Match a bunch of idioms for sign extensions, implementing InstCombine/signext.ll

llvm-svn: 23428
2005-09-24 23:43:33 +00:00
Chris Lattner 175463a165 Simplify this code a bit by relying on recursive simplification. Support
sprintf("%s", P)'s that have uses.

s/hasNUses(0)/use_empty()/

llvm-svn: 23425
2005-09-24 22:17:06 +00:00
Chris Lattner 499e33646e remove some debugging code
llvm-svn: 23411
2005-09-23 18:49:09 +00:00
Chris Lattner c59a371d45 Fold two consequtive branches that share a common destination between them.
This implements SimplifyCFG/branch-fold.ll, and is useful on ?:/min/max heavy
code

llvm-svn: 23410
2005-09-23 18:47:20 +00:00
Chris Lattner 3a978bf66d simplify some logic further
llvm-svn: 23408
2005-09-23 07:23:18 +00:00
Chris Lattner cc14ebc17b pull a bunch of logic out of SimplifyCFG into a helper fn
llvm-svn: 23407
2005-09-23 06:39:30 +00:00
Chris Lattner 6c70106053 Start threading across blocks with code in them, so long as the code does
not define a value that is used outside of it's block.  This catches many
more simplifications, e.g. 854 in 176.gcc, 137 in vpr, etc.

This implements branch-phi-thread.ll:test3.ll

llvm-svn: 23397
2005-09-20 01:48:40 +00:00
Chris Lattner f0bd8d0107 Implement merging of blocks with the same condition if the block has multiple
predecessors.  This implements branch-phi-thread.ll::test1

llvm-svn: 23395
2005-09-20 00:43:16 +00:00
Chris Lattner 049cb4482f Reject a case we don't handle yet
llvm-svn: 23393
2005-09-19 23:57:04 +00:00
Chris Lattner a160924d57 remove debugging code :-/
llvm-svn: 23392
2005-09-19 23:50:15 +00:00
Chris Lattner 748f903046 Implement SimplifyCFG/branch-phi-thread.ll, the most trivial case of threading
control across branches with determined outcomes.  More generality to follow.
This triggers a couple thousand times in specint.

llvm-svn: 23391
2005-09-19 23:49:37 +00:00
Chris Lattner b4b2530a1a Refactor this code a bit and make it more general. This now compiles:
struct S { unsigned int i : 6, j : 11, k : 15; } b;
void plus2 (unsigned int x) { b.j += x; }

To:

_plus2:
        lis r2, ha16(L_b$non_lazy_ptr)
        lwz r2, lo16(L_b$non_lazy_ptr)(r2)
        lwz r4, 0(r2)
        slwi r3, r3, 6
        add r3, r4, r3
        rlwimi r3, r4, 0, 26, 14
        stw r3, 0(r2)
        blr


instead of:

_plus2:
        lis r2, ha16(L_b$non_lazy_ptr)
        lwz r2, lo16(L_b$non_lazy_ptr)(r2)
        lwz r4, 0(r2)
        rlwinm r5, r4, 26, 21, 31
        add r3, r5, r3
        rlwimi r4, r3, 6, 15, 25
        stw r4, 0(r2)
        blr

by eliminating an 'and'.

I'm pretty sure this is as small as we can go :)

llvm-svn: 23386
2005-09-18 07:22:02 +00:00
Chris Lattner 797dee7705 Compile
struct S { unsigned int i : 6, j : 11, k : 15; } b;
void plus2 (unsigned int x) {
  b.j += x;
}

to:

plus2:
        mov %EAX, DWORD PTR [b]
        mov %ECX, %EAX
        and %ECX, 131008
        mov %EDX, DWORD PTR [%ESP + 4]
        shl %EDX, 6
        add %EDX, %ECX
        and %EDX, 131008
        and %EAX, -131009
        or %EDX, %EAX
        mov DWORD PTR [b], %EDX
        ret

instead of:

plus2:
        mov %EAX, DWORD PTR [b]
        mov %ECX, %EAX
        shr %ECX, 6
        and %ECX, 2047
        add %ECX, DWORD PTR [%ESP + 4]
        shl %ECX, 6
        and %ECX, 131008
        and %EAX, -131009
        or %ECX, %EAX
        mov DWORD PTR [b], %ECX
        ret

llvm-svn: 23385
2005-09-18 06:30:59 +00:00
Chris Lattner 01f56c68e9 Generalize this transform, using MaskedValueIsZero, allowing us to compile:
struct S { unsigned int i : 6, j : 11, k : 15; } b;
void plus3 (unsigned int x) { b.k += x; }

To:

plus3:
        mov %EAX, DWORD PTR [%ESP + 4]
        shl %EAX, 17
        add DWORD PTR [b], %EAX
        ret

instead of:

plus3:
        mov %EAX, DWORD PTR [%ESP + 4]
        shl %EAX, 17
        mov %ECX, DWORD PTR [b]
        add %EAX, %ECX
        and %EAX, -131072
        and %ECX, 131071
        or %ECX, %EAX
        mov DWORD PTR [b], %ECX
        ret

llvm-svn: 23384
2005-09-18 06:02:59 +00:00
Chris Lattner 4ebc8ab4e0 fix typeo
llvm-svn: 23383
2005-09-18 05:25:20 +00:00
Chris Lattner e5b23a6d67 Remove unintentionally committed code
llvm-svn: 23382
2005-09-18 05:12:51 +00:00
Chris Lattner 27cb9dbd35 implement shift.ll:test25. This compiles:
struct S { unsigned int i : 6, j : 11, k : 15; } b;
void plus3 (unsigned int x) {
  b.k += x;
}

to:

_plus3:
        lis r2, ha16(L_b$non_lazy_ptr)
        lwz r2, lo16(L_b$non_lazy_ptr)(r2)
        lwz r3, 0(r2)
        rlwinm r4, r3, 0, 0, 14
        add r4, r4, r3
        rlwimi r4, r3, 0, 15, 31
        stw r4, 0(r2)
        blr

instead of:

_plus3:
        lis r2, ha16(L_b$non_lazy_ptr)
        lwz r2, lo16(L_b$non_lazy_ptr)(r2)
        lwz r4, 0(r2)
        srwi r5, r4, 17
        add r3, r5, r3
        slwi r3, r3, 17
        rlwimi r3, r4, 0, 15, 31
        stw r3, 0(r2)
        blr

llvm-svn: 23381
2005-09-18 05:12:10 +00:00
Chris Lattner af517574ce Implement add.ll:test29. Codegening:
struct S { unsigned int i : 6, j : 11, k : 15; } b;
void plus1 (unsigned int x) {
  b.i += x;
}

as:
_plus1:
        lis r2, ha16(L_b$non_lazy_ptr)
        lwz r2, lo16(L_b$non_lazy_ptr)(r2)
        lwz r4, 0(r2)
        add r3, r4, r3
        rlwimi r3, r4, 0, 0, 25
        stw r3, 0(r2)
        blr

instead of:

_plus1:
        lis r2, ha16(L_b$non_lazy_ptr)
        lwz r2, lo16(L_b$non_lazy_ptr)(r2)
        lwz r4, 0(r2)
        rlwinm r5, r4, 0, 26, 31
        add r3, r5, r3
        rlwimi r3, r4, 0, 0, 25
        stw r3, 0(r2)
        blr

llvm-svn: 23379
2005-09-18 04:24:45 +00:00
Chris Lattner 027eaf01cf remove debug output
llvm-svn: 23377
2005-09-18 03:50:25 +00:00
Chris Lattner 1521298993 Implement or.ll:test21. This teaches instcombine to be able to turn this:
struct {
   unsigned int bit0:1;
   unsigned int ubyte:31;
} sdata;

void foo() {
  sdata.ubyte++;
}

into this:

foo:
        add DWORD PTR [sdata], 2
        ret

instead of this:

foo:
        mov %EAX, DWORD PTR [sdata]
        mov %ECX, %EAX
        add %ECX, 2
        and %ECX, -2
        and %EAX, 1
        or %EAX, %ECX
        mov DWORD PTR [sdata], %EAX
        ret

llvm-svn: 23376
2005-09-18 03:42:07 +00:00
Chris Lattner a393e4d4b3 Fix the regression last night compiling povray
llvm-svn: 23348
2005-09-14 17:32:56 +00:00
Chris Lattner 2a8932960d Add a simple xform to simplify array accesses with casts in the way.
This is useful for 178.galgel where resolution of dope vectors (by the
optimizer) causes the scales to become apparent.

llvm-svn: 23328
2005-09-13 18:36:04 +00:00
Chris Lattner fd018c8dfe Fix an issue where LSR would miss rewriting a use of an IV expression by a PHI node that is not the original PHI.
This fixes up a dot-product loop in galgel, speeding it up from 18.47s to
16.13s.

llvm-svn: 23327
2005-09-13 02:09:55 +00:00
Chris Lattner 567b81f0d2 Add a helper function, allowing us to simplify some code a bit, changing
indentation, no functionality change

llvm-svn: 23325
2005-09-13 00:40:14 +00:00
Chris Lattner 219175c84d Implement a simple xform to turn code like this:
if () { store A -> P; } else { store B -> P; }

into a PHI node with one store, in the most trival case.  This implements
load.ll:test10.

llvm-svn: 23324
2005-09-12 23:23:25 +00:00
Chris Lattner e0bfdf1485 Another load-peephole optimization: do gcse when two loads are next to
each other.  This implements InstCombine/load.ll:test9

llvm-svn: 23322
2005-09-12 22:21:03 +00:00
Chris Lattner b990f7d8ed Implement a trivial form of store->load forwarding where the store and the
load are exactly consequtive.  This is picked up by other passes, but this
triggers thousands of times in fortran programs that use static locals
(and is thus a compile-time speedup).

llvm-svn: 23320
2005-09-12 22:00:15 +00:00
Chris Lattner 8048b85e8f Fix a regression from last night, which caused this pass to create invalid
code for IV uses outside of loops that are not dominated by the latch block.
We should only convert these uses to use the post-inc value if they ARE
dominated by the latch block.

Also use a new LoopInfo method to simplify some code.

This fixes Transforms/LoopStrengthReduce/2005-09-12-UsesOutOutsideOfLoop.ll

llvm-svn: 23318
2005-09-12 17:11:27 +00:00
Chris Lattner a67648396a _test:
li r2, 0
LBB_test_1:     ; no_exit.2
        li r5, 0
        stw r5, 0(r3)
        addi r2, r2, 1
        addi r3, r3, 4
        cmpwi cr0, r2, 701
        blt cr0, LBB_test_1     ; no_exit.2
LBB_test_2:     ; loopexit.2.loopexit
        addi r2, r2, 1
        stw r2, 0(r4)
        blr
[zion ~/llvm]$ cat > ~/xx
Uses of IV's outside of the loop should use hte post-incremented version
of the IV, not the preincremented version.  This helps many loops (e.g. in sixtrack)
which used to generate code like this (this is the code from the
dont-hoist-simple-loop-constants.ll testcase):

_test:
        li r2, 0                 **** IV starts at 0
LBB_test_1:     ; no_exit.2
        or r5, r2, r2            **** Copy for loop exit
        li r2, 0
        stw r2, 0(r3)
        addi r3, r3, 4
        addi r2, r5, 1
        addi r6, r5, 2           **** IV+2
        cmpwi cr0, r6, 701
        blt cr0, LBB_test_1     ; no_exit.2
LBB_test_2:     ; loopexit.2.loopexit
        addi r2, r5, 2       ****  IV+2
        stw r2, 0(r4)
        blr

And now generated code like this:

_test:
        li r2, 1               *** IV starts at 1
LBB_test_1:     ; no_exit.2
        li r5, 0
        stw r5, 0(r3)
        addi r2, r2, 1
        addi r3, r3, 4
        cmpwi cr0, r2, 701     *** IV.postinc + 0
        blt cr0, LBB_test_1
LBB_test_2:     ; loopexit.2.loopexit
        stw r2, 0(r4)          *** IV.postinc + 0
        blr

llvm-svn: 23313
2005-09-12 06:04:47 +00:00
Chris Lattner 530fe6ab30 implement Transforms/LoopStrengthReduce/dont-hoist-simple-loop-constants.ll.
We used to emit this code for it:

_test:
        li r2, 1     ;; Value tying up a register for the whole loop
        li r5, 0
LBB_test_1:     ; no_exit.2
        or r6, r5, r5
        li r5, 0
        stw r5, 0(r3)
        addi r5, r6, 1
        addi r3, r3, 4
        add r7, r2, r5  ;; should be addi r7, r5, 1
        cmpwi cr0, r7, 701
        blt cr0, LBB_test_1     ; no_exit.2
LBB_test_2:     ; loopexit.2.loopexit
        addi r2, r6, 2
        stw r2, 0(r4)
        blr

now we emit this:

_test:
        li r2, 0
LBB_test_1:     ; no_exit.2
        or r5, r2, r2
        li r2, 0
        stw r2, 0(r3)
        addi r3, r3, 4
        addi r2, r5, 1
        addi r6, r5, 2   ;; whoa, fold those adds!
        cmpwi cr0, r6, 701
        blt cr0, LBB_test_1     ; no_exit.2
LBB_test_2:     ; loopexit.2.loopexit
        addi r2, r5, 2
        stw r2, 0(r4)
        blr

more improvement coming.

llvm-svn: 23306
2005-09-10 01:18:45 +00:00
Chris Lattner b5e381a8cf Fix a problem that Dan Berlin noticed, where reassociation would not succeed
in building maximal expressions before simplifying them.  In particular, i
cases like this:

X-(A+B+X)

the code would consider A+B+X to be a maximal expression (not understanding
that the single use '-' would be turned into a + later), simplify it (a noop)
then later get simplified again.

Each of these simplify steps is where the cost of reassociation comes from,
so this patch should speed up the already fast pass a bit.

Thanks to Dan for noticing this!

llvm-svn: 23214
2005-09-02 07:07:58 +00:00
Chris Lattner 9fe263aa75 Avoid creating garbage instructions, just move the old add instruction
to where we need it when converting -(A+B+C) -> -A + -B + -C.

llvm-svn: 23213
2005-09-02 06:38:04 +00:00
Chris Lattner d1325da091 add some assertions and fix problems where reassociate could access the
Ops vector out of range

llvm-svn: 23211
2005-09-02 05:23:22 +00:00
Chris Lattner 8ca5b2a6d2 Fix Regression/Transforms/Reassociate/2005-08-24-Crash.ll
llvm-svn: 23019
2005-08-24 17:55:32 +00:00
Chris Lattner 4201cd1bbc Transform floor((double)FLT) -> (double)floorf(FLT), implementing
Regression/Transforms/SimplifyLibCalls/floor.ll.  This triggers 19 times in
177.mesa.

llvm-svn: 23017
2005-08-24 17:22:17 +00:00
Chris Lattner ea7dfd53d6 Fix Transforms/LoopStrengthReduce/2005-08-17-OutOfLoopVariant.ll, a crash
on 177.mesa

llvm-svn: 22843
2005-08-17 21:22:41 +00:00
Chris Lattner 2bf7cb5213 Use a new helper to split critical edges, making the code simpler.
Do not claim to not change the CFG.  We do change the cfg to split critical
edges.  This isn't causing us a problem now, but could likely do so in the
future.

llvm-svn: 22824
2005-08-17 06:35:16 +00:00
Chris Lattner 5cf983ee0f Fix a bad case in gzip where we put lots of things in registers across the
loop, because a IV-dependent value was used outside of the loop and didn't
have immediate-folding capability

llvm-svn: 22798
2005-08-16 00:38:11 +00:00
Chris Lattner 47d3ec3525 Ooops, don't forget to clear this. The real inner loop is now:
.LBB_foo_3:     ; no_exit.1
        lfd f2, 0(r9)
        lfd f3, 8(r9)
        fmul f4, f1, f2
        fmadd f4, f0, f3, f4
        stfd f4, 8(r9)
        fmul f3, f1, f3
        fmsub f2, f0, f2, f3
        stfd f2, 0(r9)
        addi r9, r9, 16
        addi r8, r8, 1
        cmpw cr0, r8, r4
        ble .LBB_foo_3  ; no_exit.1

llvm-svn: 22782
2005-08-13 07:42:01 +00:00
Chris Lattner 5949d49032 Recursively scan scev expressions for common subexpressions. This allows us
to handle nested loops much better, for example, by being able to tell that
these two expressions:

{( 8 + ( 16 * ( 1 +  %Tmp11 +  %Tmp12)) +  %c_),+,( 16 *  %Tmp 12)}<loopentry.1>

{(( 16 * ( 1 +  %Tmp11 +  %Tmp12)) +  %c_),+,( 16 *  %Tmp12)}<loopentry.1>

Have the following common part that can be shared:
{(( 16 * ( 1 +  %Tmp11 +  %Tmp12)) +  %c_),+,( 16 *  %Tmp12)}<loopentry.1>

This allows us to codegen an important inner loop in 168.wupwise as:

.LBB_foo_4:     ; no_exit.1
        lfd f2, 16(r9)
        fmul f3, f0, f2
        fmul f2, f1, f2
        fadd f4, f3, f2
        stfd f4, 8(r9)
        fsub f2, f3, f2
        stfd f2, 16(r9)
        addi r8, r8, 1
        addi r9, r9, 16
        cmpw cr0, r8, r4
        ble .LBB_foo_4  ; no_exit.1

instead of:

.LBB_foo_3:     ; no_exit.1
        lfdx f2, r6, r9
        add r10, r6, r9
        lfd f3, 8(r10)
        fmul f4, f1, f2
        fmadd f4, f0, f3, f4
        stfd f4, 8(r10)
        fmul f3, f1, f3
        fmsub f2, f0, f2, f3
        stfdx f2, r6, r9
        addi r9, r9, 16
        addi r8, r8, 1
        cmpw cr0, r8, r4
        ble .LBB_foo_3  ; no_exit.1

llvm-svn: 22781
2005-08-13 07:27:18 +00:00
Chris Lattner 89c1dfc733 Teach SplitCriticalEdge to update LoopInfo if it is alive. This fixes
a problem in LoopStrengthReduction, where it would split critical edges
then confused itself with outdated loop information.

llvm-svn: 22776
2005-08-13 01:38:43 +00:00
Chris Lattner 79396539d3 remove dead code. The exit block list is computed on demand, thus does not
need to be updated.  This code is a relic from when it did.

llvm-svn: 22775
2005-08-13 01:30:36 +00:00
Chris Lattner 8447b49526 When splitting critical edges, make sure not to leave the new block in the
middle of the loop.  This turns a critical loop in gzip into this:

.LBB_test_1:    ; loopentry
        or r27, r28, r28
        add r28, r3, r27
        lhz r28, 3(r28)
        add r26, r4, r27
        lhz r26, 3(r26)
        cmpw cr0, r28, r26
        bne .LBB_test_8 ; loopentry.loopexit_crit_edge
.LBB_test_2:    ; shortcirc_next.0
        add r28, r3, r27
        lhz r28, 5(r28)
        add r26, r4, r27
        lhz r26, 5(r26)
        cmpw cr0, r28, r26
        bne .LBB_test_7 ; shortcirc_next.0.loopexit_crit_edge
.LBB_test_3:    ; shortcirc_next.1
        add r28, r3, r27
        lhz r28, 7(r28)
        add r26, r4, r27
        lhz r26, 7(r26)
        cmpw cr0, r28, r26
        bne .LBB_test_6 ; shortcirc_next.1.loopexit_crit_edge
.LBB_test_4:    ; shortcirc_next.2
        add r28, r3, r27
        lhz r26, 9(r28)
        add r28, r4, r27
        lhz r25, 9(r28)
        addi r28, r27, 8
        cmpw cr7, r26, r25
        mfcr r26, 1
        rlwinm r26, r26, 31, 31, 31
        add r25, r8, r27
        cmpw cr7, r25, r7
        mfcr r25, 1
        rlwinm r25, r25, 29, 31, 31
        and. r26, r26, r25
        bne .LBB_test_1 ; loopentry

instead of this:

.LBB_test_1:    ; loopentry
        or r27, r28, r28
        add r28, r3, r27
        lhz r28, 3(r28)
        add r26, r4, r27
        lhz r26, 3(r26)
        cmpw cr0, r28, r26
        beq .LBB_test_3 ; shortcirc_next.0
.LBB_test_2:    ; loopentry.loopexit_crit_edge
        add r2, r30, r27
        add r8, r29, r27
        b .LBB_test_9   ; loopexit
.LBB_test_3:    ; shortcirc_next.0
        add r28, r3, r27
        lhz r28, 5(r28)
        add r26, r4, r27
        lhz r26, 5(r26)
        cmpw cr0, r28, r26
        beq .LBB_test_5 ; shortcirc_next.1
.LBB_test_4:    ; shortcirc_next.0.loopexit_crit_edge
        add r2, r11, r27
        add r8, r12, r27
        b .LBB_test_9   ; loopexit
.LBB_test_5:    ; shortcirc_next.1
        add r28, r3, r27
        lhz r28, 7(r28)
        add r26, r4, r27
        lhz r26, 7(r26)
        cmpw cr0, r28, r26
        beq .LBB_test_7 ; shortcirc_next.2
.LBB_test_6:    ; shortcirc_next.1.loopexit_crit_edge
        add r2, r9, r27
        add r8, r10, r27
        b .LBB_test_9   ; loopexit
.LBB_test_7:    ; shortcirc_next.2
        add r28, r3, r27
        lhz r26, 9(r28)
        add r28, r4, r27
        lhz r25, 9(r28)
        addi r28, r27, 8
        cmpw cr7, r26, r25
        mfcr r26, 1
        rlwinm r26, r26, 31, 31, 31
        add r25, r8, r27
        cmpw cr7, r25, r7
        mfcr r25, 1
        rlwinm r25, r25, 29, 31, 31
        and. r26, r26, r25
        bne .LBB_test_1 ; loopentry

Next up, improve the code for the loop.

llvm-svn: 22769
2005-08-12 22:22:17 +00:00
Chris Lattner 4fec86d348 Fix a FIXME: if we are inserting code for a PHI argument, split the critical
edge so that the code is not always executed for both operands.  This
prevents LSR from inserting code into loops whose exit blocks contain
PHI uses of IV expressions (which are outside of loops).  On gzip, for
example, we turn this ugly code:

.LBB_test_1:    ; loopentry
        add r27, r3, r28
        lhz r27, 3(r27)
        add r26, r4, r28
        lhz r26, 3(r26)
        add r25, r30, r28    ;; Only live if exiting the loop
        add r24, r29, r28    ;; Only live if exiting the loop
        cmpw cr0, r27, r26
        bne .LBB_test_5 ; loopexit

into this:

.LBB_test_1:    ; loopentry
        or r27, r28, r28
        add r28, r3, r27
        lhz r28, 3(r28)
        add r26, r4, r27
        lhz r26, 3(r26)
        cmpw cr0, r28, r26
        beq .LBB_test_3 ; shortcirc_next.0
.LBB_test_2:    ; loopentry.loopexit_crit_edge
        add r2, r30, r27
        add r8, r29, r27
        b .LBB_test_9   ; loopexit
.LBB_test_2:    ; shortcirc_next.0
        ...
        blt .LBB_test_1


into this:

.LBB_test_1:    ; loopentry
        or r27, r28, r28
        add r28, r3, r27
        lhz r28, 3(r28)
        add r26, r4, r27
        lhz r26, 3(r26)
        cmpw cr0, r28, r26
        beq .LBB_test_3 ; shortcirc_next.0
.LBB_test_2:    ; loopentry.loopexit_crit_edge
        add r2, r30, r27
        add r8, r29, r27
        b .LBB_t_3:    ; shortcirc_next.0
.LBB_test_3:    ; shortcirc_next.0
        ...
        blt .LBB_test_1


Next step: get the block out of the loop so that the loop is all
fall-throughs again.

llvm-svn: 22766
2005-08-12 22:06:11 +00:00
Chris Lattner b7ebe65c56 Change break critical edges to not remove, then insert, PHI node entries.
Instead, just update the BB in-place.  This is both faster, and it prevents
split-critical-edges from shuffling the PHI argument list unneccesarily.

llvm-svn: 22765
2005-08-12 21:58:07 +00:00
Chris Lattner 62df798919 remove some trickiness that broke yacr2 and some other programs last night
llvm-svn: 22751
2005-08-10 17:15:20 +00:00
Chris Lattner f83ce5faee Make loop-simplify produce better loops by turning PHI nodes like X = phi [X, Y]
into just Y.  This often occurs when it seperates loops that have collapsed loop
headers.  This implements LoopSimplify/phi-node-simplify.ll

llvm-svn: 22746
2005-08-10 02:07:32 +00:00
Chris Lattner 677d85784a Allow indvar simplify to canonicalize ANY affine IV, not just affine IVs with
constant stride.  This implements Transforms/IndVarsSimplify/variable-stride-ivs.ll

llvm-svn: 22744
2005-08-10 01:12:06 +00:00
Chris Lattner edff91a49a Teach LSR to strength reduce IVs that have a loop-invariant but non-constant stride.
For code like this:

void foo(float *a, float *b, int n, int stride_a, int stride_b) {
  int i;
  for (i=0; i<n; i++)
      a[i*stride_a] = b[i*stride_b];
}

we now emit:

.LBB_foo2_2:    ; no_exit
        lfs f0, 0(r4)
        stfs f0, 0(r3)
        addi r7, r7, 1
        add r4, r2, r4
        add r3, r6, r3
        cmpw cr0, r7, r5
        blt .LBB_foo2_2 ; no_exit

instead of:

.LBB_foo_2:     ; no_exit
        mullw r8, r2, r7     ;; multiply!
        slwi r8, r8, 2
        lfsx f0, r4, r8
        mullw r8, r2, r6     ;; multiply!
        slwi r8, r8, 2
        stfsx f0, r3, r8
        addi r2, r2, 1
        cmpw cr0, r2, r5
        blt .LBB_foo_2  ; no_exit

loops with variable strides occur pretty often.  For example, in SPECFP2K
there are 317 variable strides in 177.mesa, 3 in 179.art, 14 in 188.ammp,
56 in 168.wupwise, 36 in 172.mgrid.

Now we can allow indvars to turn functions written like this:

void foo2(float *a, float *b, int n, int stride_a, int stride_b) {
  int i, ai = 0, bi = 0;
  for (i=0; i<n; i++)
    {
      a[ai] = b[bi];
      ai += stride_a;
      bi += stride_b;
    }
}

into code like the above for better analysis.  With this patch, they generate
identical code.

llvm-svn: 22740
2005-08-10 00:45:21 +00:00
Chris Lattner dde7dc525e Fix Regression/Transforms/LoopStrengthReduce/phi_node_update_multiple_preds.ll
by being more careful about updating PHI nodes

llvm-svn: 22739
2005-08-10 00:35:32 +00:00
Chris Lattner c6c4d99a21 Fix some 80 column violations.
Once we compute the evolution for a GEP, tell SE about it.  This allows users
of the GEP to know it, if the users are not direct.  This allows us to compile
this testcase:

void fbSolidFillmmx(int w, unsigned char *d) {
    while (w >= 64) {
        *(unsigned long long *) (d +  0) = 0;
        *(unsigned long long *) (d +  8) = 0;
        *(unsigned long long *) (d + 16) = 0;
        *(unsigned long long *) (d + 24) = 0;
        *(unsigned long long *) (d + 32) = 0;
        *(unsigned long long *) (d + 40) = 0;
        *(unsigned long long *) (d + 48) = 0;
        *(unsigned long long *) (d + 56) = 0;
        w -= 64;
        d += 64;
    }
}

into:

.LBB_fbSolidFillmmx_2:  ; no_exit
        li r2, 0
        stw r2, 0(r4)
        stw r2, 4(r4)
        stw r2, 8(r4)
        stw r2, 12(r4)
        stw r2, 16(r4)
        stw r2, 20(r4)
        stw r2, 24(r4)
        stw r2, 28(r4)
        stw r2, 32(r4)
        stw r2, 36(r4)
        stw r2, 40(r4)
        stw r2, 44(r4)
        stw r2, 48(r4)
        stw r2, 52(r4)
        stw r2, 56(r4)
        stw r2, 60(r4)
        addi r4, r4, 64
        addi r3, r3, -64
        cmpwi cr0, r3, 63
        bgt .LBB_fbSolidFillmmx_2       ; no_exit

instead of:

.LBB_fbSolidFillmmx_2:  ; no_exit
        li r11, 0
        stw r11, 0(r4)
        stw r11, 4(r4)
        stwx r11, r10, r4
        add r12, r10, r4
        stw r11, 4(r12)
        stwx r11, r9, r4
        add r12, r9, r4
        stw r11, 4(r12)
        stwx r11, r8, r4
        add r12, r8, r4
        stw r11, 4(r12)
        stwx r11, r7, r4
        add r12, r7, r4
        stw r11, 4(r12)
        stwx r11, r6, r4
        add r12, r6, r4
        stw r11, 4(r12)
        stwx r11, r5, r4
        add r12, r5, r4
        stw r11, 4(r12)
        stwx r11, r2, r4
        add r12, r2, r4
        stw r11, 4(r12)
        addi r4, r4, 64
        addi r3, r3, -64
        cmpwi cr0, r3, 63
        bgt .LBB_fbSolidFillmmx_2       ; no_exit

llvm-svn: 22737
2005-08-09 23:39:36 +00:00
Chris Lattner 02742710f3 SCEVAddExpr::get() of an empty list is invalid.
llvm-svn: 22724
2005-08-09 01:13:47 +00:00
Chris Lattner a091ff1764 Implement: LoopStrengthReduce/share_ivs.ll
Two changes:
  * Only insert one PHI node for each stride.  Other values are live in
    values.  This cannot introduce higher register pressure than the
    previous approach, and can take advantage of reg+reg addressing modes.
  * Factor common base values out of uses before moving values from the
    base to the immediate fields.  This improves codegen by starting the
    stride-specific PHI node out at a common place for each IV use.

As an example, we used to generate this for a loop in swim:

.LBB_main_no_exit_2E_6_2E_i_no_exit_2E_7_2E_i_2:        ; no_exit.7.i
        lfd f0, 0(r8)
        stfd f0, 0(r3)
        lfd f0, 0(r6)
        stfd f0, 0(r7)
        lfd f0, 0(r2)
        stfd f0, 0(r5)
        addi r9, r9, 1
        addi r2, r2, 8
        addi r5, r5, 8
        addi r6, r6, 8
        addi r7, r7, 8
        addi r8, r8, 8
        addi r3, r3, 8
        cmpw cr0, r9, r4
        bgt .LBB_main_no_exit_2E_6_2E_i_no_exit_2E_7_2E_i_1

now we emit:

.LBB_main_no_exit_2E_6_2E_i_no_exit_2E_7_2E_i_2:        ; no_exit.7.i
        lfdx f0, r8, r2
        stfdx f0, r9, r2
        lfdx f0, r5, r2
        stfdx f0, r7, r2
        lfdx f0, r3, r2
        stfdx f0, r6, r2
        addi r10, r10, 1
        addi r2, r2, 8
        cmpw cr0, r10, r4
        bgt .LBB_main_no_exit_2E_6_2E_i_no_exit_2E_7_2E_i_1

As another more dramatic example, we used to emit this:

.LBB_main_L_90_no_exit_2E_0_2E_i16_no_exit_2E_1_2E_i19_2:       ; no_exit.1.i19
        lfd f0, 8(r21)
        lfd f4, 8(r3)
        lfd f5, 8(r27)
        lfd f6, 8(r22)
        lfd f7, 8(r5)
        lfd f8, 8(r6)
        lfd f9, 8(r30)
        lfd f10, 8(r11)
        lfd f11, 8(r12)
        fsub f10, f10, f11
        fadd f5, f4, f5
        fmul f5, f5, f1
        fadd f6, f6, f7
        fadd f6, f6, f8
        fadd f6, f6, f9
        fmadd f0, f5, f6, f0
        fnmsub f0, f10, f2, f0
        stfd f0, 8(r4)
        lfd f0, 8(r25)
        lfd f5, 8(r26)
        lfd f6, 8(r23)
        lfd f9, 8(r28)
        lfd f10, 8(r10)
        lfd f12, 8(r9)
        lfd f13, 8(r29)
        fsub f11, f13, f11
        fadd f4, f4, f5
        fmul f4, f4, f1
        fadd f5, f6, f9
        fadd f5, f5, f10
        fadd f5, f5, f12
        fnmsub f0, f4, f5, f0
        fnmsub f0, f11, f3, f0
        stfd f0, 8(r24)
        lfd f0, 8(r8)
        fsub f4, f7, f8
        fsub f5, f12, f10
        fnmsub f0, f5, f2, f0
        fnmsub f0, f4, f3, f0
        stfd f0, 8(r2)
        addi r20, r20, 1
        addi r2, r2, 8
        addi r8, r8, 8
        addi r10, r10, 8
        addi r12, r12, 8
        addi r6, r6, 8
        addi r29, r29, 8
        addi r28, r28, 8
        addi r26, r26, 8
        addi r25, r25, 8
        addi r24, r24, 8
        addi r5, r5, 8
        addi r23, r23, 8
        addi r22, r22, 8
        addi r3, r3, 8
        addi r9, r9, 8
        addi r11, r11, 8
        addi r30, r30, 8
        addi r27, r27, 8
        addi r21, r21, 8
        addi r4, r4, 8
        cmpw cr0, r20, r7
        bgt .LBB_main_L_90_no_exit_2E_0_2E_i16_no_exit_2E_1_2E_i19_1

we now emit:

.LBB_main_L_90_no_exit_2E_0_2E_i16_no_exit_2E_1_2E_i19_2:       ; no_exit.1.i19
        lfdx f0, r21, r20
        lfdx f4, r3, r20
        lfdx f5, r27, r20
        lfdx f6, r22, r20
        lfdx f7, r5, r20
        lfdx f8, r6, r20
        lfdx f9, r30, r20
        lfdx f10, r11, r20
        lfdx f11, r12, r20
        fsub f10, f10, f11
        fadd f5, f4, f5
        fmul f5, f5, f1
        fadd f6, f6, f7
        fadd f6, f6, f8
        fadd f6, f6, f9
        fmadd f0, f5, f6, f0
        fnmsub f0, f10, f2, f0
        stfdx f0, r4, r20
        lfdx f0, r25, r20
        lfdx f5, r26, r20
        lfdx f6, r23, r20
        lfdx f9, r28, r20
        lfdx f10, r10, r20
        lfdx f12, r9, r20
        lfdx f13, r29, r20
        fsub f11, f13, f11
        fadd f4, f4, f5
        fmul f4, f4, f1
        fadd f5, f6, f9
        fadd f5, f5, f10
        fadd f5, f5, f12
        fnmsub f0, f4, f5, f0
        fnmsub f0, f11, f3, f0
        stfdx f0, r24, r20
        lfdx f0, r8, r20
        fsub f4, f7, f8
        fsub f5, f12, f10
        fnmsub f0, f5, f2, f0
        fnmsub f0, f4, f3, f0
        stfdx f0, r2, r20
        addi r19, r19, 1
        addi r20, r20, 8
        cmpw cr0, r19, r7
        bgt .LBB_main_L_90_no_exit_2E_0_2E_i16_no_exit_2E_1_2E_i19_1

llvm-svn: 22722
2005-08-09 00:18:09 +00:00
Chris Lattner 37c24cc98c Suck the base value out of the UsersToProcess vector into the BasedUser
class to simplify the code.  Fuse two loops.

llvm-svn: 22721
2005-08-08 22:56:21 +00:00
Chris Lattner 37ed895bf1 Split MoveLoopVariantsToImediateField out from MoveImmediateValues. The
first is a correctness thing, and the later is an optzn thing.  This also
is needed to support a future change.

llvm-svn: 22720
2005-08-08 22:32:34 +00:00
Chris Lattner 9f269e40c9 Use the new 'moveBefore' method to simplify some code. Really, which is
easier to understand?  :)

llvm-svn: 22706
2005-08-08 19:11:57 +00:00
Chris Lattner 14203e85b2 Not all constants are legal immediates in load/store instructions.
llvm-svn: 22704
2005-08-08 06:25:50 +00:00
Chris Lattner c70bbc0c41 Implement LoopStrengthReduce/share_code_in_preheader.ll by having one
rewriter for all code inserted into the preheader, which is never flushed.

llvm-svn: 22702
2005-08-08 05:47:49 +00:00
Chris Lattner 9bfa6f8784 Implement a simple optimization for the termination condition of the loop.
The termination condition actually wants to use the post-incremented value
of the loop, not a new indvar with an unusual base.

On PPC, for example, this allows us to compile
LoopStrengthReduce/exit_compare_live_range.ll to:

_foo:
        li r2, 0
.LBB_foo_1:     ; no_exit
        li r5, 0
        stw r5, 0(r3)
        addi r2, r2, 1
        cmpw cr0, r2, r4
        bne .LBB_foo_1  ; no_exit
        blr

instead of:

_foo:
        li r2, 1                ;; IV starts at 1, not 0
.LBB_foo_1:     ; no_exit
        li r5, 0
        stw r5, 0(r3)
        addi r5, r2, 1
        cmpw cr0, r2, r4
        or r2, r5, r5           ;; Reg-reg copy, extra live range
        bne .LBB_foo_1  ; no_exit
        blr

This implements LoopStrengthReduce/exit_compare_live_range.ll

llvm-svn: 22699
2005-08-08 05:28:22 +00:00
Chris Lattner 579b20b747 All stats are "Number of ..."
llvm-svn: 22694
2005-08-07 20:02:04 +00:00
Chris Lattner 2c14cf7b74 Add some simple folds that occur in bitfield cases. Fix a minor bug in
isHighOnes, where it would consider 0 to have high ones.

llvm-svn: 22693
2005-08-07 07:03:10 +00:00
Chris Lattner 134ebd0801 Fix typoCVS: ----------------------------------------------------------------------
llvm-svn: 22692
2005-08-07 07:00:52 +00:00
Chris Lattner f4dd8c445c * Use the new PHINode::hasConstantValue method to simplify some code
* Teach this code to move allocas out of the loop when tail call eliminating
  a call marked 'tail'.  This implements TailCallElim/move_alloca_for_tail_call.ll
* Do not perform this transformation if a call is marked 'tail' and if there
  are allocas that we cannot move out of the loop in #2.  Doing so would increase
  the stack usage of the function.  This implements fixes
  PR615 and TailCallElim/dont-tce-tail-marked-call.ll.

llvm-svn: 22690
2005-08-07 04:27:41 +00:00
Chris Lattner 11e7a5eda7 Make sure to clean CastedPointers after casts are potentially deleted.
This fixes LSR crashes on 301.apsi, 191.fma3d, and 189.lucas

llvm-svn: 22673
2005-08-05 01:30:11 +00:00
Chris Lattner 9f9c260b8c now that hasConstantValue defaults to only returning values that dominate
the PHI node, this ugly code can vanish.

llvm-svn: 22672
2005-08-05 01:04:30 +00:00
Chris Lattner 257efb2ad3 This code can handle non-dominating instructions
llvm-svn: 22667
2005-08-05 00:57:45 +00:00
Nate Begeman b392321cae Fix a fixme in CondPropagate.cpp by moving a PhiNode optimization into
BasicBlock's removePredecessor routine.  This requires shuffling around
the definition and implementation of hasContantValue from Utils.h,cpp into
Instructions.h,cpp

llvm-svn: 22664
2005-08-04 23:24:19 +00:00
Chris Lattner 45f8b6e7aa Modify how immediates are removed from base expressions to deal with the fact
that the symbolic evaluator is not always able to use subtraction to remove
expressions.  This makes the code faster, and fixes the last crash on 178.galgel.
Finally, add a statistic to see how many phi nodes are inserted.

On 178.galgel, we get the follow stats:

2562 loop-reduce  - Number of PHIs inserted
3927 loop-reduce  - Number of GEPs strength reduced

llvm-svn: 22662
2005-08-04 22:34:05 +00:00
Chris Lattner a6d7c355bc * Refactor some code into a new BasedUser::RewriteInstructionToUseNewBase
method.
* Fix a crash on 178.galgel, where we would insert expressions before PHI
  nodes instead of into the PHI node predecessor blocks.

llvm-svn: 22657
2005-08-04 20:03:32 +00:00
Chris Lattner 0f7c0fa2a7 Fix a case that caused this to crash on 178.galgel
llvm-svn: 22653
2005-08-04 19:26:19 +00:00
Chris Lattner acc42c4df1 Teach LSR about loop-variant expressions, such as loops like this:
for (i = 0; i < N; ++i)
    A[i][foo()] = 0;

here we still want to strength reduce the A[i] part, even though foo() is
l-v.

This also simplifies some of the 'CanReduce' logic.

This implements Transforms/LoopStrengthReduce/ops_after_indvar.ll

llvm-svn: 22652
2005-08-04 19:08:16 +00:00
Nate Begeman 456044b724 Remove some more dead code.
llvm-svn: 22650
2005-08-04 18:13:56 +00:00
Chris Lattner eaf24725b2 Refactor this code substantially with the following improvements:
1. We only analyze instructions once, guaranteed
  2. AnalyzeGetElementPtrUsers has been ripped apart and replaced with
     something much simpler.

The next step is to handle expressions that are not all indvar+loop-invariant
values (e.g. handling indvar+loopvariant).

llvm-svn: 22649
2005-08-04 17:40:30 +00:00
Chris Lattner 6f286b760f refactor some code
llvm-svn: 22643
2005-08-04 01:19:13 +00:00
Chris Lattner 6510749050 invert to if's to make the logic simpler
llvm-svn: 22641
2005-08-04 00:40:47 +00:00
Chris Lattner a0102fbc4f When processing outer loops and we find uses of an IV in inner loops, make
sure to handle the use, just don't recurse into it.

This permits us to generate this code for a simple nested loop case:

.LBB_foo_0:     ; entry
        stwu r1, -48(r1)
        stw r29, 44(r1)
        stw r30, 40(r1)
        mflr r11
        stw r11, 56(r1)
        lis r2, ha16(L_A$non_lazy_ptr)
        lwz r30, lo16(L_A$non_lazy_ptr)(r2)
        li r29, 1
.LBB_foo_1:     ; no_exit.0
        bl L_bar$stub
        li r2, 1
        or r3, r30, r30
.LBB_foo_2:     ; no_exit.1
        lfd f0, 8(r3)
        stfd f0, 0(r3)
        addi r4, r2, 1
        addi r3, r3, 8
        cmpwi cr0, r2, 100
        or r2, r4, r4
        bne .LBB_foo_2  ; no_exit.1
.LBB_foo_3:     ; loopexit.1
        addi r30, r30, 800
        addi r2, r29, 1
        cmpwi cr0, r29, 100
        or r29, r2, r2
        bne .LBB_foo_1  ; no_exit.0
.LBB_foo_4:     ; return
        lwz r11, 56(r1)
        mtlr r11
        lwz r30, 40(r1)
        lwz r29, 44(r1)
        lwz r1, 0(r1)
        blr

instead of this:

_foo:
.LBB_foo_0:     ; entry
        stwu r1, -48(r1)
        stw r28, 44(r1)                   ;; uses an extra register.
        stw r29, 40(r1)
        stw r30, 36(r1)
        mflr r11
        stw r11, 56(r1)
        li r30, 1
        li r29, 0
        or r28, r29, r29
.LBB_foo_1:     ; no_exit.0
        bl L_bar$stub
        mulli r2, r28, 800           ;; unstrength-reduced multiply
        lis r3, ha16(L_A$non_lazy_ptr)   ;; loop invariant address computation
        lwz r3, lo16(L_A$non_lazy_ptr)(r3)
        add r2, r2, r3
        mulli r4, r29, 800           ;; unstrength-reduced multiply
        addi r3, r3, 8
        add r3, r4, r3
        li r4, 1
.LBB_foo_2:     ; no_exit.1
        lfd f0, 0(r3)
        stfd f0, 0(r2)
        addi r5, r4, 1
        addi r2, r2, 8                 ;; multiple stride 8 IV's
        addi r3, r3, 8
        cmpwi cr0, r4, 100
        or r4, r5, r5
        bne .LBB_foo_2  ; no_exit.1
.LBB_foo_3:     ; loopexit.1
        addi r28, r28, 1               ;;; Many IV's with stride 1
        addi r29, r29, 1
        addi r2, r30, 1
        cmpwi cr0, r30, 100
        or r30, r2, r2
        bne .LBB_foo_1  ; no_exit.0
.LBB_foo_4:     ; return
        lwz r11, 56(r1)
        mtlr r11
        lwz r30, 36(r1)
        lwz r29, 40(r1)
        lwz r28, 44(r1)
        lwz r1, 0(r1)
        blr

llvm-svn: 22640
2005-08-04 00:14:11 +00:00
Chris Lattner fc62470466 Teach loop-reduce to see into nested loops, to pull out immediate values
pushed down by SCEV.

In a nested loop case, this allows us to emit this:

        lis r3, ha16(L_A$non_lazy_ptr)
        lwz r3, lo16(L_A$non_lazy_ptr)(r3)
        add r2, r2, r3
        li r3, 1
.LBB_foo_2:     ; no_exit.1
        lfd f0, 8(r2)        ;; Uses offset of 8 instead of 0
        stfd f0, 0(r2)
        addi r4, r3, 1
        addi r2, r2, 8
        cmpwi cr0, r3, 100
        or r3, r4, r4
        bne .LBB_foo_2  ; no_exit.1

instead of this:

        lis r3, ha16(L_A$non_lazy_ptr)
        lwz r3, lo16(L_A$non_lazy_ptr)(r3)
        add r2, r2, r3
        addi r3, r3, 8
        li r4, 1
.LBB_foo_2:     ; no_exit.1
        lfd f0, 0(r3)
        stfd f0, 0(r2)
        addi r5, r4, 1
        addi r2, r2, 8
        addi r3, r3, 8
        cmpwi cr0, r4, 100
        or r4, r5, r5
        bne .LBB_foo_2  ; no_exit.1

llvm-svn: 22639
2005-08-03 23:44:42 +00:00
Chris Lattner bb78c97e24 improve debug output
llvm-svn: 22638
2005-08-03 23:30:08 +00:00
Chris Lattner db23c74e5e Move from Stage 0 to Stage 1.
Only emit one PHI node for IV uses with identical bases and strides (after
moving foldable immediates to the load/store instruction).

This implements LoopStrengthReduce/dont_insert_redundant_ops.ll, allowing
us to generate this PPC code for test1:

        or r30, r3, r3
.LBB_test1_1:   ; Loop
        li r2, 0
        stw r2, 0(r30)
        stw r2, 4(r30)
        bl L_pred$stub
        addi r30, r30, 8
        cmplwi cr0, r3, 0
        bne .LBB_test1_1        ; Loop

instead of this code:

        or r30, r3, r3
        or r29, r3, r3
.LBB_test1_1:   ; Loop
        li r2, 0
        stw r2, 0(r29)
        stw r2, 4(r30)
        bl L_pred$stub
        addi r30, r30, 8        ;; Two iv's with step of 8
        addi r29, r29, 8
        cmplwi cr0, r3, 0
        bne .LBB_test1_1        ; Loop

llvm-svn: 22635
2005-08-03 22:51:21 +00:00
Chris Lattner 430d0022df Rename IVUse to IVUsersOfOneStride, use a struct instead of a pair to
unify some parallel vectors and get field names more descriptive than
"first" and "second".  This isn't lisp afterall :)

llvm-svn: 22633
2005-08-03 22:21:05 +00:00
Chris Lattner 84e9baa925 Fix a nasty dangling pointer issue. The ScalarEvolution pass would keep a
map from instruction* to SCEVHandles.  When we delete instructions, we have
to tell it about it.  We would run into nasty cases where new instructions
were reallocated at old instruction addresses and get the old map values.
Bad bad bad :(

llvm-svn: 22632
2005-08-03 21:36:09 +00:00
Chris Lattner 3de05cc930 The correct fix for PR612, which also fixes
Transforms/LowerInvoke/2005-08-03-InvokeWithPHIUse.ll

llvm-svn: 22628
2005-08-03 18:51:44 +00:00
Chris Lattner f8a81a9886 When inserting code, make sure not to insert it before PHI nodes. This
fixes PR612 and Transforms/LowerInvoke/2005-08-03-InvokeWithPHI.ll

llvm-svn: 22626
2005-08-03 18:34:29 +00:00
Chris Lattner d683bdd0f8 Fix Transforms/SimplifyCFG/2005-08-03-PHIFactorCrash.ll, a problem that
occurred while bugpointing another testcase

llvm-svn: 22621
2005-08-03 17:59:45 +00:00
Chris Lattner 2dbf1960ff Finally, add the required constraint checks to fix Transforms/SimplifyCFG/2005-08-01-PHIUpdateFail.ll
the right way

llvm-svn: 22615
2005-08-03 00:59:12 +00:00