[llvm-commits] [llvm] r42309 - in /llvm/trunk: lib/Transforms/Scalar/LoopIndexSplit.cpp test/Transforms/LoopIndexSplit/2007-09-25-UpdateIterationSpace-2.ll

[Devang Patel]

Author: dpatel
Date: Tue Sep 25 13:24:48 2007
New Revision: 42309

URL: http://llvm.org/viewvc/llvm-project?rev=42309&view=rev
Log:
Handle multiple induction variables.
This fixes PR714.

Added:
    llvm/trunk/test/Transforms/LoopIndexSplit/2007-09-25-UpdateIterationSpace-2.ll
Modified:
    llvm/trunk/lib/Transforms/Scalar/LoopIndexSplit.cpp

Modified: llvm/trunk/lib/Transforms/Scalar/LoopIndexSplit.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/LoopIndexSplit.cpp?rev=42309&r1=42308&r2=42309&view=diff

==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/LoopIndexSplit.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/LoopIndexSplit.cpp Tue Sep 25 13:24:48 2007
@@ -676,7 +676,7 @@
       continue;
 
     // Check if I is induction variable increment instruction.
-    if (!IndVarIncrement && I->getOpcode() == Instruction::Add) {
+    if (I->getOpcode() == Instruction::Add) {
 
       Value *Op0 = I->getOperand(0);
       Value *Op1 = I->getOperand(1);
@@ -685,16 +685,23 @@
 
       if ((PN = dyn_cast<PHINode>(Op0))) {
         if ((CI = dyn_cast<ConstantInt>(Op1)))
-          IndVarIncrement = I;
+          if (CI->isOne()) {
+            if (!IndVarIncrement && PN == IndVar)
+              IndVarIncrement = I;
+            // else this is another loop induction variable
+            continue;
+          }
       } else 
         if ((PN = dyn_cast<PHINode>(Op1))) {
           if ((CI = dyn_cast<ConstantInt>(Op0)))
-            IndVarIncrement = I;
+            if (CI->isOne()) {
+              if (!IndVarIncrement && PN == IndVar)
+                IndVarIncrement = I;
+              // else this is another loop induction variable
+              continue;
+            }
       }
-          
-      if (IndVarIncrement && PN == IndVar && CI->isOne())
-        continue;
-    }
+    } 
 
     // I is an Exit condition if next instruction is block terminator.
     // Exit condition is OK if it compares loop invariant exit value,

Added: llvm/trunk/test/Transforms/LoopIndexSplit/2007-09-25-UpdateIterationSpace-2.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/LoopIndexSplit/2007-09-25-UpdateIterationSpace-2.ll?rev=42309&view=auto

==============================================================================
--- llvm/trunk/test/Transforms/LoopIndexSplit/2007-09-25-UpdateIterationSpace-2.ll (added)
+++ llvm/trunk/test/Transforms/LoopIndexSplit/2007-09-25-UpdateIterationSpace-2.ll Tue Sep 25 13:24:48 2007
@@ -0,0 +1,59 @@
+; PR714
+; Update loop iteraton space to eliminate condition inside loop.
+; RUN: llvm-as < %s | opt -loop-index-split | llvm-dis | not grep bothcond
+define void @test(float* %x, i32 %ndat, float** %y, float %xcen, i32 %xmin, i32 %xmax, float %sigmal, float %contribution) {
+entry:
+	%tmp5310 = icmp sgt i32 %xmin, %xmax		; <i1> [#uses=1]
+	br i1 %tmp5310, label %return, label %bb.preheader
+
+bb.preheader:		; preds = %entry
+	%tmp3031 = fpext float %contribution to double		; <double> [#uses=1]
+	%tmp32 = mul double %tmp3031, 5.000000e-01		; <double> [#uses=1]
+	%tmp3839 = fpext float %sigmal to double		; <double> [#uses=1]
+	br label %bb
+
+bb:		; preds = %bb.preheader, %cond_next45
+	%i.01.0 = phi i32 [ %tmp47, %cond_next45 ], [ %xmin, %bb.preheader ]		; <i32> [#uses=4]
+	%k.06.0 = phi i32 [ %tmp49, %cond_next45 ], [ 0, %bb.preheader ]		; <i32> [#uses=3]
+	%tmp2 = icmp sgt i32 %i.01.0, -1		; <i1> [#uses=1]
+	%tmp6 = icmp slt i32 %i.01.0, %ndat		; <i1> [#uses=1]
+	%bothcond = and i1 %tmp2, %tmp6		; <i1> [#uses=1]
+	br i1 %bothcond, label %cond_true9, label %cond_next45
+
+cond_true9:		; preds = %bb
+	%tmp12 = getelementptr float* %x, i32 %i.01.0		; <float*> [#uses=1]
+	%tmp13 = load float* %tmp12, align 4		; <float> [#uses=1]
+	%tmp15 = sub float %xcen, %tmp13		; <float> [#uses=1]
+	%tmp16 = tail call float @fabsf( float %tmp15 )		; <float> [#uses=1]
+	%tmp18 = fdiv float %tmp16, %sigmal		; <float> [#uses=1]
+	%tmp21 = load float** %y, align 4		; <float*> [#uses=2]
+	%tmp27 = getelementptr float* %tmp21, i32 %k.06.0		; <float*> [#uses=1]
+	%tmp28 = load float* %tmp27, align 4		; <float> [#uses=1]
+	%tmp2829 = fpext float %tmp28 to double		; <double> [#uses=1]
+	%tmp34 = sub float -0.000000e+00, %tmp18		; <float> [#uses=1]
+	%tmp3435 = fpext float %tmp34 to double		; <double> [#uses=1]
+	%tmp36 = tail call double @exp( double %tmp3435 )		; <double> [#uses=1]
+	%tmp37 = mul double %tmp32, %tmp36		; <double> [#uses=1]
+	%tmp40 = fdiv double %tmp37, %tmp3839		; <double> [#uses=1]
+	%tmp41 = add double %tmp2829, %tmp40		; <double> [#uses=1]
+	%tmp4142 = fptrunc double %tmp41 to float		; <float> [#uses=1]
+	%tmp44 = getelementptr float* %tmp21, i32 %k.06.0		; <float*> [#uses=1]
+	store float %tmp4142, float* %tmp44, align 4
+	br label %cond_next45
+
+cond_next45:		; preds = %bb, %cond_true9
+	%tmp47 = add i32 %i.01.0, 1		; <i32> [#uses=2]
+	%tmp49 = add i32 %k.06.0, 1		; <i32> [#uses=1]
+	%tmp53 = icmp sgt i32 %tmp47, %xmax		; <i1> [#uses=1]
+	br i1 %tmp53, label %return.loopexit, label %bb
+
+return.loopexit:		; preds = %cond_next45
+	br label %return
+
+return:		; preds = %return.loopexit, %entry
+	ret void
+}
+
+declare float @fabsf(float)
+
+declare double @exp(double)