Fix strange logic in CollectIVUsers used to determine whether all uses are

addresses, part 1. This fixes an obvious logic bug. Previously if the only
in-loop use is a PHI, it would return AllUsesAreAddresses as true.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65178 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evan Cheng 2009-02-20 22:16:49 +00:00
parent ff518c86f7
commit d33cec18a9
2 changed files with 52 additions and 1 deletions

View File

@ -1439,6 +1439,7 @@ SCEVHandle LoopStrengthReduce::CollectIVUsers(const SCEVHandle &Stride,
// fields of the BasedUsers. We do this so that it increases the commonality
// of the remaining uses.
unsigned NumPHI = 0;
bool HasAddress = false;
for (unsigned i = 0, e = UsersToProcess.size(); i != e; ++i) {
// If the user is not in the current loop, this means it is using the exit
// value of the IV. Do not put anything in the base, make sure it's all in
@ -1449,7 +1450,6 @@ SCEVHandle LoopStrengthReduce::CollectIVUsers(const SCEVHandle &Stride,
UsersToProcess[i].Base =
SE->getIntegerSCEV(0, UsersToProcess[i].Base->getType());
} else {
// Addressing modes can be folded into loads and stores. Be careful that
// the store is through the expression, not of the expression though.
bool isPHI = false;
@ -1462,6 +1462,9 @@ SCEVHandle LoopStrengthReduce::CollectIVUsers(const SCEVHandle &Stride,
// Not all uses are outside the loop.
AllUsesAreOutsideLoop = false;
if (isAddress)
HasAddress = true;
// If this use isn't an address, then not all uses are addresses.
if (!isAddress && !isPHI)
@ -1478,6 +1481,10 @@ SCEVHandle LoopStrengthReduce::CollectIVUsers(const SCEVHandle &Stride,
if (NumPHI > 1)
AllUsesAreAddresses = false;
// There are no in-loop address uses.
if (AllUsesAreAddresses && (!HasAddress && !AllUsesAreOutsideLoop))
AllUsesAreAddresses = false;
return CommonExprs;
}

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@ -0,0 +1,44 @@
; RUN: llvm-as < %s | llc -march=x86 | not grep imul
target triple = "i386-apple-darwin9.6"
%struct.III_psy_xmin = type { [22 x double], [13 x [3 x double]] }
%struct.III_scalefac_t = type { [22 x i32], [13 x [3 x i32]] }
%struct.gr_info = type { i32, i32, i32, i32, i32, i32, i32, i32, [3 x i32], [3 x i32], i32, i32, i32, i32, i32, i32, i32, i32, i32, i32*, [4 x i32] }
%struct.lame_global_flags = type { i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i8*, i8*, i32, i32, float, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, float, i32, i32, i32, float, float, float, float, i32, i32, i32, i32, i32, i32, i32, i32 }
define fastcc void @outer_loop(%struct.lame_global_flags* nocapture %gfp, double* nocapture %xr, i32 %targ_bits, double* nocapture %best_noise, %struct.III_psy_xmin* nocapture %l3_xmin, i32* nocapture %l3_enc, %struct.III_scalefac_t* nocapture %scalefac, %struct.gr_info* nocapture %cod_info, i32 %ch) nounwind {
entry:
br label %bb4
bb4: ; preds = %bb4, %entry
br i1 true, label %bb5, label %bb4
bb5: ; preds = %bb4
br i1 true, label %bb28.i37, label %bb.i4
bb.i4: ; preds = %bb.i4, %bb5
br label %bb.i4
bb28.i37: ; preds = %bb33.i47, %bb5
%i.1.reg2mem.0.i = phi i32 [ %0, %bb33.i47 ], [ 0, %bb5 ] ; <i32> [#uses=2]
%0 = add i32 %i.1.reg2mem.0.i, 1 ; <i32> [#uses=2]
br label %bb29.i38
bb29.i38: ; preds = %bb33.i47, %bb28.i37
%indvar32.i = phi i32 [ %indvar.next33.i, %bb33.i47 ], [ 0, %bb28.i37 ] ; <i32> [#uses=2]
%sfb.314.i = add i32 %indvar32.i, 0 ; <i32> [#uses=3]
%1 = getelementptr [4 x [21 x double]]* null, i32 0, i32 %0, i32 %sfb.314.i ; <double*> [#uses=1]
%2 = load double* %1, align 8 ; <double> [#uses=0]
br i1 false, label %bb30.i41, label %bb33.i47
bb30.i41: ; preds = %bb29.i38
%3 = getelementptr %struct.III_scalefac_t* null, i32 0, i32 1, i32 %sfb.314.i, i32 %i.1.reg2mem.0.i ; <i32*> [#uses=1]
store i32 0, i32* %3, align 4
br label %bb33.i47
bb33.i47: ; preds = %bb30.i41, %bb29.i38
%4 = add i32 %sfb.314.i, 1 ; <i32> [#uses=1]
%phitmp.i46 = icmp ugt i32 %4, 11 ; <i1> [#uses=1]
%indvar.next33.i = add i32 %indvar32.i, 1 ; <i32> [#uses=1]
br i1 %phitmp.i46, label %bb28.i37, label %bb29.i38
}