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2005-09-26Add a simple interpreter to this code, allowing us to statically evaluateChris Lattner
global ctors that are simple enough. This implements ctor-list-opt.ll:CTOR2. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23437 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-26factor some code into a InstallGlobalCtors method, add comments. No ↵Chris Lattner
functionality change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23435 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-26Make the global opt optimizer work on modules with a null terminator, byChris Lattner
accepting the null even with a non-65535 init prio git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23434 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-26Factor this code out into a few methods.Chris Lattner
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. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23433 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-25Fix some logic I broke that caused a regression onChris Lattner
SimplifyLibCalls/2005-05-20-sprintf-crash.ll git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23430 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-24Move MaskedValueIsZero up.Chris Lattner
Match a bunch of idioms for sign extensions, implementing InstCombine/signext.ll git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23428 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-24Simplify this code a bit by relying on recursive simplification. SupportChris Lattner
sprintf("%s", P)'s that have uses. s/hasNUses(0)/use_empty()/ git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23425 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-23remove some debugging codeChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23411 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-23Fold two consequtive branches that share a common destination between them.Chris Lattner
This implements SimplifyCFG/branch-fold.ll, and is useful on ?:/min/max heavy code git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23410 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-23simplify some logic furtherChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23408 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-23pull a bunch of logic out of SimplifyCFG into a helper fnChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23407 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-20Start threading across blocks with code in them, so long as the code doesChris Lattner
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 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23397 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-20Implement merging of blocks with the same condition if the block has multipleChris Lattner
predecessors. This implements branch-phi-thread.ll::test1 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23395 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-19Reject a case we don't handle yetChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23393 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-19remove debugging code :-/Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23392 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-19Implement SimplifyCFG/branch-phi-thread.ll, the most trivial case of threadingChris Lattner
control across branches with determined outcomes. More generality to follow. This triggers a couple thousand times in specint. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23391 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-18Refactor this code a bit and make it more general. This now compiles:Chris Lattner
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 :) git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23386 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-18CompileChris Lattner
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 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23385 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-18Generalize this transform, using MaskedValueIsZero, allowing us to compile:Chris Lattner
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 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23384 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-18fix typeoChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23383 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-18Remove unintentionally committed codeChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23382 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-18implement shift.ll:test25. This compiles:Chris Lattner
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 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23381 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-18Implement add.ll:test29. Codegening:Chris Lattner
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 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23379 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-18remove debug outputChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23377 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-18Implement or.ll:test21. This teaches instcombine to be able to turn this:Chris Lattner
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 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23376 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-14Fix the regression last night compiling povrayChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23348 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-13Add a simple xform to simplify array accesses with casts in the way.Chris Lattner
This is useful for 178.galgel where resolution of dope vectors (by the optimizer) causes the scales to become apparent. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23328 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
2005-09-13Add a helper function, allowing us to simplify some code a bit, changingChris Lattner
indentation, no functionality change git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23325 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-12Implement a simple xform to turn code like this:Chris Lattner
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. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23324 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-12Another load-peephole optimization: do gcse when two loads are next toChris Lattner
each other. This implements InstCombine/load.ll:test9 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23322 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-12Implement a trivial form of store->load forwarding where the store and theChris Lattner
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). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23320 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
2005-09-02Fix a problem that Dan Berlin noticed, where reassociation would not succeedChris Lattner
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! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23214 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-02Avoid creating garbage instructions, just move the old add instructionChris Lattner
to where we need it when converting -(A+B+C) -> -A + -B + -C. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23213 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-02add some assertions and fix problems where reassociate could access theChris Lattner
Ops vector out of range git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23211 91177308-0d34-0410-b5e6-96231b3b80d8
2005-08-24Fix Regression/Transforms/Reassociate/2005-08-24-Crash.llChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23019 91177308-0d34-0410-b5e6-96231b3b80d8
2005-08-24Transform floor((double)FLT) -> (double)floorf(FLT), implementingChris Lattner
Regression/Transforms/SimplifyLibCalls/floor.ll. This triggers 19 times in 177.mesa. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23017 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
2005-08-13Teach SplitCriticalEdge to update LoopInfo if it is alive. This fixesChris Lattner
a problem in LoopStrengthReduction, where it would split critical edges then confused itself with outdated loop information. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22776 91177308-0d34-0410-b5e6-96231b3b80d8
2005-08-13remove dead code. The exit block list is computed on demand, thus does notChris Lattner
need to be updated. This code is a relic from when it did. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22775 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
2005-08-12Change break critical edges to not remove, then insert, PHI node entries.Chris Lattner
Instead, just update the BB in-place. This is both faster, and it prevents split-critical-edges from shuffling the PHI argument list unneccesarily. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22765 91177308-0d34-0410-b5e6-96231b3b80d8