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path: root/lib/Transforms/Scalar/LoopStrengthReduce.cpp
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2006-11-26Removed #include <iostream> and replaced with llvm_* streams.Bill Wendling
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31923 91177308-0d34-0410-b5e6-96231b3b80d8
2006-11-17If an indvar with a variable stride is used by the exit condition, go aheadChris Lattner
and handle it like constant stride vars. This fixes some bad codegen in variable stride cases. For example, it compiles this: void foo(int k, int i) { for (k=i+i; k <= 8192; k+=i) flags2[k] = 0; } to: LBB1_1: #bb.preheader movl %eax, %ecx addl %ecx, %ecx movl L_flags2$non_lazy_ptr, %edx LBB1_2: #bb movb $0, (%edx,%ecx) addl %eax, %ecx cmpl $8192, %ecx jle LBB1_2 #bb LBB1_5: #return ret or (if the array is local and we are in dynamic-nonpic or static mode): LBB3_2: #bb movb $0, _flags2(%ecx) addl %eax, %ecx cmpl $8192, %ecx jle LBB3_2 #bb and: lis r2, ha16(L_flags2$non_lazy_ptr) lwz r2, lo16(L_flags2$non_lazy_ptr)(r2) slwi r3, r4, 1 LBB1_2: ;bb li r5, 0 add r6, r4, r3 stbx r5, r2, r3 cmpwi cr0, r6, 8192 bgt cr0, LBB1_5 ;return instead of: leal (%eax,%eax,2), %ecx movl %eax, %edx addl %edx, %edx addl L_flags2$non_lazy_ptr, %edx xorl %esi, %esi LBB1_2: #bb movb $0, (%edx,%esi) movl %eax, %edi addl %esi, %edi addl %ecx, %esi cmpl $8192, %esi jg LBB1_5 #return and: lis r2, ha16(L_flags2$non_lazy_ptr) lwz r2, lo16(L_flags2$non_lazy_ptr)(r2) mulli r3, r4, 3 slwi r5, r4, 1 li r6, 0 add r2, r2, r5 LBB1_2: ;bb li r5, 0 add r7, r3, r6 stbx r5, r2, r6 add r6, r4, r6 cmpwi cr0, r7, 8192 ble cr0, LBB1_2 ;bb This speeds up Benchmarks/Shootout/sieve from 8.533s to 6.464s and implements LoopStrengthReduce/var_stride_used_by_compare.ll git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31809 91177308-0d34-0410-b5e6-96231b3b80d8
2006-11-02For PR786:Reid Spencer
Turn on -Wunused and -Wno-unused-parameter. Clean up most of the resulting fall out by removing unused variables. Remaining warnings have to do with unused functions (I didn't want to delete code without review) and unused variables in generated code. Maintainers should clean up the remaining issues when they see them. All changes pass DejaGnu tests and Olden. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31380 91177308-0d34-0410-b5e6-96231b3b80d8
2006-10-28break edges more intelligentlyChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31257 91177308-0d34-0410-b5e6-96231b3b80d8
2006-10-28prepare for a change I'm about to makeChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31248 91177308-0d34-0410-b5e6-96231b3b80d8
2006-10-20For PR950:Reid Spencer
This patch implements the first increment for the Signless Types feature. All changes pertain to removing the ConstantSInt and ConstantUInt classes in favor of just using ConstantInt. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31063 91177308-0d34-0410-b5e6-96231b3b80d8
2006-08-27eliminate RegisterOpt. It does the same thing as RegisterPass.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29925 91177308-0d34-0410-b5e6-96231b3b80d8
2006-08-27s|llvm/Support/Visibility.h|llvm/Support/Compiler.h|Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29911 91177308-0d34-0410-b5e6-96231b3b80d8
2006-08-03Changes:Chris Lattner
1. Update an obsolete comment. 2. Make the sorting by base an explicit (though still N^2) step, so that the code is more clear on what it is doing. 3. Partition uses so that uses inside the loop are handled before uses outside the loop. Note that none of these changes currently changes the code inserted by LSR, but they are a stepping stone to getting there. This code is the result of some crazy pair programming with Nate. :) git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29493 91177308-0d34-0410-b5e6-96231b3b80d8
2006-07-18Only reuse a previous IV if it would not require a type conversion.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29186 91177308-0d34-0410-b5e6-96231b3b80d8
2006-06-28Use hidden visibility to make symbols in an anonymous namespace getChris Lattner
dropped. This shrinks libllvmgcc.dylib another 67K git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28975 91177308-0d34-0410-b5e6-96231b3b80d8
2006-06-09RewriteExpr, either the new PHI node of induction variable or theEvan Cheng
post-increment value, should be first cast to the appropriated type (to the type of the common expr). Otherwise, the rewrite of a use based on (common + iv) may end up with an incorrect type. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28735 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-12Get rid of a signed/unsigned compare warning.Reid Spencer
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27625 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-24Fix spelloChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27052 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-22silence a bogus gcc warningChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26953 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-18- Fixed a bogus if condition.Evan Cheng
- Added more debugging info. - Allow reuse of IV of negative stride. e.g. -4 stride == 2 * iv of -2 stride. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26841 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-18Sort StrideOrder so we can process the smallest strides first. This allowsEvan Cheng
for more IV reuses. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26837 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-17Allow users of iv / stride to be rewritten with expression that is a multiplyEvan Cheng
of a smaller stride even if they have a common loop invariant expression part. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26828 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-16For each loop, keep track of all the IV expressions inserted indexed byEvan Cheng
stride. For a set of uses of the IV of a stride which is a multiple of another stride, do not insert a new IV expression. Rather, reuse the previous IV and rewrite the uses as uses of IV expression multiplied by the factor. e.g. x = 0 ...; x ++ y = 0 ...; y += 4 then use of y can be rewritten as use of 4*x for x86. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26803 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-13Added target lowering hooks which LSR consults to make more intelligentEvan Cheng
transformation decisions. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26738 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-04Use SCEVExpander::InsertCastOfTo instead of our own code. This reducesChris Lattner
#LLVM LOC, and auto-cse's cast instructions. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25974 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-04Fix two significant bugs in LSR:Chris Lattner
1. When rewriting code in outer loops, sometimes we would insert code into inner loops that is invariant in that loop. 2. Notice that 4*(2+x) is 8+4*x and use that to simplify expressions. This is a performance neutral change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25964 91177308-0d34-0410-b5e6-96231b3b80d8
2006-01-22Make iostream #inclusion explicitChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25514 91177308-0d34-0410-b5e6-96231b3b80d8
2006-01-11Switch these to using ETForest instead of DominatorSet to compute itself.Chris Lattner
Patch written by Daniel Berlin! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25202 91177308-0d34-0410-b5e6-96231b3b80d8
2005-12-05getRawValue zero extens for unsigned values, use getsextvalue so that weChris Lattner
know that small negative values fit into the immediate field of addressing modes. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@24608 91177308-0d34-0410-b5e6-96231b3b80d8
2005-10-21My previous patch was too conservative. Reject FP and void types, but doChris Lattner
allow pointer types. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23859 91177308-0d34-0410-b5e6-96231b3b80d8
2005-10-20Do NOT touch FP ops with LSR. This fixes a testcase Nate sent me from anChris Lattner
inner loop like this: LBB_RateConvertMono8AltiVec_2: ; no_exit lis r2, ha16(.CPI_RateConvertMono8AltiVec_0) lfs f3, lo16(.CPI_RateConvertMono8AltiVec_0)(r2) fmr f3, f3 fadd f0, f2, f0 fadd f3, f0, f3 fcmpu cr0, f3, f1 bge cr0, LBB_RateConvertMono8AltiVec_2 ; no_exit to an inner loop like this: LBB_RateConvertMono8AltiVec_1: ; no_exit fsub f2, f2, f1 fcmpu cr0, f2, f1 fmr f0, f2 bge cr0, LBB_RateConvertMono8AltiVec_1 ; no_exit Doh! good catch! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23838 91177308-0d34-0410-b5e6-96231b3b80d8
2005-10-11Fix (hopefully the last) issue where LSR is nondeterminstic. When pullingChris Lattner
out CSE's of base expressions it could build a result whose order was nondet. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23698 91177308-0d34-0410-b5e6-96231b3b80d8
2005-10-11Fix another problem where LSR was being nondeterminstic. Also remove elementsChris Lattner
from the end of a vector instead of the beginning git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23697 91177308-0d34-0410-b5e6-96231b3b80d8
2005-10-11Fix another lsr-is-nondeterministic caseChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23695 91177308-0d34-0410-b5e6-96231b3b80d8
2005-10-09Hrm, you didn't see this.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23673 91177308-0d34-0410-b5e6-96231b3b80d8
2005-10-09Fix a source of non-determinism in the backend: the order of processingChris Lattner
IV strides dependend on the pointer order of the strides in memory. Non-determinism is bad. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23672 91177308-0d34-0410-b5e6-96231b3b80d8
2005-10-03Make IVUseShouldUsePostIncValue more aggressive when the use is a PHI. InChris Lattner
particular, it should realize that phi's use their values in the pred block not the phi block itself. This change turns our em3d loop from this: _test: cmpwi cr0, r4, 0 bgt cr0, LBB_test_2 ; entry.no_exit_crit_edge LBB_test_1: ; entry.loopexit_crit_edge li r2, 0 b LBB_test_6 ; loopexit LBB_test_2: ; entry.no_exit_crit_edge li r6, 0 LBB_test_3: ; no_exit or r2, r6, r6 lwz r6, 0(r3) cmpw cr0, r6, r5 beq cr0, LBB_test_6 ; loopexit LBB_test_4: ; endif addi r3, r3, 4 addi r6, r2, 1 cmpw cr0, r6, r4 blt cr0, LBB_test_3 ; no_exit LBB_test_5: ; endif.loopexit.loopexit_crit_edge addi r3, r2, 1 blr LBB_test_6: ; loopexit or r3, r2, r2 blr into: _test: cmpwi cr0, r4, 0 bgt cr0, LBB_test_2 ; entry.no_exit_crit_edge LBB_test_1: ; entry.loopexit_crit_edge li r2, 0 b LBB_test_5 ; loopexit LBB_test_2: ; entry.no_exit_crit_edge li r6, 0 LBB_test_3: ; no_exit lwz r2, 0(r3) cmpw cr0, r2, r5 or r2, r6, r6 beq cr0, LBB_test_5 ; loopexit LBB_test_4: ; endif addi r3, r3, 4 addi r6, r6, 1 cmpw cr0, r6, r4 or r2, r6, r6 blt cr0, LBB_test_3 ; no_exit LBB_test_5: ; loopexit or r3, r2, r2 blr Unfortunately, this is actually worse code, because the register coallescer is getting confused somehow. If it were doing its job right, it could turn the code into this: _test: cmpwi cr0, r4, 0 bgt cr0, LBB_test_2 ; entry.no_exit_crit_edge LBB_test_1: ; entry.loopexit_crit_edge li r6, 0 b LBB_test_5 ; loopexit LBB_test_2: ; entry.no_exit_crit_edge li r6, 0 LBB_test_3: ; no_exit lwz r2, 0(r3) cmpw cr0, r2, r5 beq cr0, LBB_test_5 ; loopexit LBB_test_4: ; endif addi r3, r3, 4 addi r6, r6, 1 cmpw cr0, r6, r4 blt cr0, LBB_test_3 ; no_exit LBB_test_5: ; loopexit or r3, r6, r6 blr ... which I'll work on next. :) git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23604 91177308-0d34-0410-b5e6-96231b3b80d8
2005-10-03Refactor some code into a functionChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23603 91177308-0d34-0410-b5e6-96231b3b80d8
2005-10-03This break is bogus and I have no idea why it was there. Basically it preventsChris Lattner
memoizing code when IV's are used by phinodes outside of loops. In a simple example, we were getting this code before (note that r6 and r7 are isomorphic IV's): li r6, 0 or r7, r6, r6 LBB_test_3: ; no_exit lwz r2, 0(r3) cmpw cr0, r2, r5 or r2, r7, r7 beq cr0, LBB_test_5 ; loopexit LBB_test_4: ; endif addi r2, r7, 1 addi r7, r7, 1 addi r3, r3, 4 addi r6, r6, 1 cmpw cr0, r6, r4 blt cr0, LBB_test_3 ; no_exit Now we get: li r6, 0 LBB_test_3: ; no_exit or r2, r6, r6 lwz r6, 0(r3) cmpw cr0, r6, r5 beq cr0, LBB_test_6 ; loopexit LBB_test_4: ; endif addi r3, r3, 4 addi r6, r2, 1 cmpw cr0, r6, r4 blt cr0, LBB_test_3 ; no_exit this was noticed in em3d. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23602 91177308-0d34-0410-b5e6-96231b3b80d8
2005-10-03when checking if we should move a split edge block outside of a loop,Chris Lattner
check the presplit pred, not the post-split pred. This was causing us to make the wrong decision in some cases, leaving the critical edge block in the loop. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23601 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-27Make the pass name simplerChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23476 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-13Fix an issue where LSR would miss rewriting a use of an IV expression by a ↵Chris Lattner
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. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23327 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-12Fix a regression from last night, which caused this pass to create invalidChris Lattner
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 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23318 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-12_test:Chris Lattner
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 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23313 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-10implement Transforms/LoopStrengthReduce/dont-hoist-simple-loop-constants.ll.Chris Lattner
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. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23306 91177308-0d34-0410-b5e6-96231b3b80d8
2005-08-17Fix Transforms/LoopStrengthReduce/2005-08-17-OutOfLoopVariant.ll, a crashChris Lattner
on 177.mesa git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22843 91177308-0d34-0410-b5e6-96231b3b80d8
2005-08-17Use a new helper to split critical edges, making the code simpler.Chris Lattner
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. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22824 91177308-0d34-0410-b5e6-96231b3b80d8
2005-08-16Fix a bad case in gzip where we put lots of things in registers across theChris Lattner
loop, because a IV-dependent value was used outside of the loop and didn't have immediate-folding capability git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22798 91177308-0d34-0410-b5e6-96231b3b80d8
2005-08-13Ooops, don't forget to clear this. The real inner loop is now:Chris Lattner
.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 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22782 91177308-0d34-0410-b5e6-96231b3b80d8
2005-08-13Recursively scan scev expressions for common subexpressions. This allows usChris Lattner
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 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22781 91177308-0d34-0410-b5e6-96231b3b80d8
2005-08-12When splitting critical edges, make sure not to leave the new block in theChris Lattner
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. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22769 91177308-0d34-0410-b5e6-96231b3b80d8
2005-08-12Fix a FIXME: if we are inserting code for a PHI argument, split the criticalChris Lattner
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. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22766 91177308-0d34-0410-b5e6-96231b3b80d8
2005-08-10Teach LSR to strength reduce IVs that have a loop-invariant but non-constant ↵Chris Lattner
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. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22740 91177308-0d34-0410-b5e6-96231b3b80d8
2005-08-10Fix Regression/Transforms/LoopStrengthReduce/phi_node_update_multiple_preds.llChris Lattner
by being more careful about updating PHI nodes git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22739 91177308-0d34-0410-b5e6-96231b3b80d8
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