In cases where a pointer value is an operand of a multiplication or

division operation, don't attempt to use the operation's value as
the base of a getelementptr. This fixes PR4271.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72422 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Analysis/ScalarEvolutionExpander.cpp b/lib/Analysis/ScalarEvolutionExpander.cpp
index 191fcc02c4b032dfb552a8034b48d6750ea2b335..6992b998802d96ad3cabea40d41bd3d6e535a6b2 100644 (file)
--- a/lib/Analysis/ScalarEvolutionExpander.cpp
+++ b/lib/Analysis/ScalarEvolutionExpander.cpp
@@ -448,9 +448,14 @@ Value *SCEVExpander::visitAddRecExpr(const SCEVAddRecExpr *S) {
       ExposePointerBase(Base, RestArray[0], SE);
       // If we found a pointer, expand the AddRec with a GEP.
       if (const PointerType *PTy = dyn_cast<PointerType>(Base->getType())) {
-        Value *StartV = expand(Base);
-        assert(StartV->getType() == PTy && "Pointer type mismatch for GEP!");
-        return expandAddToGEP(RestArray, RestArray+1, PTy, Ty, StartV);
+        // Make sure the Base isn't something exotic, such as a multiplied
+        // or divided pointer value. In those cases, the result type isn't
+        // actually a pointer type.
+        if (!isa<SCEVMulExpr>(Base) && !isa<SCEVUDivExpr>(Base)) {
+          Value *StartV = expand(Base);
+          assert(StartV->getType() == PTy && "Pointer type mismatch for GEP!");
+          return expandAddToGEP(RestArray, RestArray+1, PTy, Ty, StartV);
+        }
       }
     }
 

diff --git a/test/Transforms/IndVarSimplify/divide-pointer.ll b/test/Transforms/IndVarSimplify/divide-pointer.ll
new file mode 100644 (file)
index 0000000..747d47e
--- /dev/null
+++ b/test/Transforms/IndVarSimplify/divide-pointer.ll
@@ -0,0 +1,95 @@
+; RUN: llvm-as < %s | opt -indvars
+; PR4271
+
+target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
+target triple = "i386-apple-darwin10.0"
+       %struct.xyz = type <{ i64, i64, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i64, [8 x i8], i64, i64, i32, i32, [4 x i32], i32, i32, i32, i32, i32, i32, [76 x i32], i32, [2 x %struct.uvw] }>
+       %struct.uvw = type <{ i64, i64 }>
+
+define i32 @foo(%struct.xyz* %header, i8* %p2, i8* %p3, i8* nocapture %p4) nounwind {
+entry:
+       br label %while.body.i
+
+while.body.i:          ; preds = %while.body.i, %entry
+       br i1 undef, label %while.body.i, label %bcopy_internal.exit
+
+bcopy_internal.exit:           ; preds = %while.body.i
+       %conv135 = ptrtoint %struct.xyz* %header to i32         ; <i32> [#uses=1]
+       %shr136 = lshr i32 %conv135, 12         ; <i32> [#uses=1]
+       br label %for.body
+
+for.body:              ; preds = %for.body, %bcopy_internal.exit
+       %ppnum.052 = phi i32 [ %inc, %for.body ], [ %shr136, %bcopy_internal.exit ]             ; <i32> [#uses=1]
+       %inc = add i32 %ppnum.052, 1            ; <i32> [#uses=2]
+       %cmp = icmp ugt i32 %inc, undef         ; <i1> [#uses=1]
+       br i1 %cmp, label %if.then199, label %for.body
+
+if.then199:            ; preds = %if.then199, %for.body
+       br label %if.then199
+}
+
+define i32 @same_thing_but_signed(%struct.xyz* %header, i8* %p2, i8* %p3, i8* nocapture %p4) nounwind {
+entry:
+       br label %while.body.i
+
+while.body.i:          ; preds = %while.body.i, %entry
+       br i1 undef, label %while.body.i, label %bcopy_internal.exit
+
+bcopy_internal.exit:           ; preds = %while.body.i
+       %conv135 = ptrtoint %struct.xyz* %header to i32         ; <i32> [#uses=1]
+       %shr136 = ashr i32 %conv135, 12         ; <i32> [#uses=1]
+       br label %for.body
+
+for.body:              ; preds = %for.body, %bcopy_internal.exit
+       %ppnum.052 = phi i32 [ %inc, %for.body ], [ %shr136, %bcopy_internal.exit ]             ; <i32> [#uses=1]
+       %inc = add i32 %ppnum.052, 1            ; <i32> [#uses=2]
+       %cmp = icmp ugt i32 %inc, undef         ; <i1> [#uses=1]
+       br i1 %cmp, label %if.then199, label %for.body
+
+if.then199:            ; preds = %if.then199, %for.body
+       br label %if.then199
+}
+
+define i32 @same_thing_but_multiplied(%struct.xyz* %header, i8* %p2, i8* %p3, i8* nocapture %p4) nounwind {
+entry:
+       br label %while.body.i
+
+while.body.i:          ; preds = %while.body.i, %entry
+       br i1 undef, label %while.body.i, label %bcopy_internal.exit
+
+bcopy_internal.exit:           ; preds = %while.body.i
+       %conv135 = ptrtoint %struct.xyz* %header to i32         ; <i32> [#uses=1]
+       %shr136 = shl i32 %conv135, 12          ; <i32> [#uses=1]
+       br label %for.body
+
+for.body:              ; preds = %for.body, %bcopy_internal.exit
+       %ppnum.052 = phi i32 [ %inc, %for.body ], [ %shr136, %bcopy_internal.exit ]             ; <i32> [#uses=1]
+       %inc = add i32 %ppnum.052, 1            ; <i32> [#uses=2]
+       %cmp = icmp ugt i32 %inc, undef         ; <i1> [#uses=1]
+       br i1 %cmp, label %if.then199, label %for.body
+
+if.then199:            ; preds = %if.then199, %for.body
+       br label %if.then199
+}
+
+define i32 @same_thing_but_xored(%struct.xyz* %header, i8* %p2, i8* %p3, i8* nocapture %p4) nounwind {
+entry:
+       br label %while.body.i
+
+while.body.i:          ; preds = %while.body.i, %entry
+       br i1 undef, label %while.body.i, label %bcopy_internal.exit
+
+bcopy_internal.exit:           ; preds = %while.body.i
+       %conv135 = ptrtoint %struct.xyz* %header to i32         ; <i32> [#uses=1]
+       %shr136 = xor i32 %conv135, 12          ; <i32> [#uses=1]
+       br label %for.body
+
+for.body:              ; preds = %for.body, %bcopy_internal.exit
+       %ppnum.052 = phi i32 [ %inc, %for.body ], [ %shr136, %bcopy_internal.exit ]             ; <i32> [#uses=1]
+       %inc = add i32 %ppnum.052, 1            ; <i32> [#uses=2]
+       %cmp = icmp ugt i32 %inc, undef         ; <i1> [#uses=1]
+       br i1 %cmp, label %if.then199, label %for.body
+
+if.then199:            ; preds = %if.then199, %for.body
+       br label %if.then199
+}