; RUN: opt -S < %s -analyze -scalar-evolution -loop-simplify -scalar-evolution -enable-new-pm=0 | FileCheck %s ; RUN: opt -S < %s -passes='print,loop-simplify,print' 2>&1 | FileCheck %s ; Provide legal integer types. target datalayout = "n8:16:32:64" @maxStat = external global i32 ; LoopSimplify should invalidate SCEV when splitting out the ; inner loop. ; ; First SCEV print: ; CHECK-LABEL: Classifying expressions for: @test ; CHECK: %[[PHI:.*]] = phi i32 [ 0, %entry ], [ %{{.*}}, %if.then5 ], [ %[[PHI]], %if.end ] ; CHECK-LABEL: Determining loop execution counts for: @test ; CHECK: Loop %for.body18: Unpredictable backedge-taken count. ; CHECK: Loop %for.body18: max backedge-taken count is 2147483646 ; CHECK: Loop %for.body18: Unpredictable predicated backedge-taken count. ; CHECK: Loop %for.cond: Unpredictable backedge-taken count. ; CHECK: Loop %for.cond: Unpredictable max backedge-taken count. ; CHECK: Loop %for.cond: Unpredictable predicated backedge-taken count. ; ; Now simplify the loop, which should cause SCEV to re-compute more precise ; info here in addition to having preheader PHIs. Second SCEV print: ; CHECK-LABEL: Classifying expressions for: @test ; CHECK: phi i32 [ %{{.*}}, %if.then5 ], [ 0, %entry ] ; CHECK-LABEL: Determining loop execution counts for: @test ; CHECK: Loop %for.body18: Unpredictable backedge-taken count. ; CHECK: Loop %for.body18: max backedge-taken count is 2147483646 ; CHECK: Loop %for.body18: Unpredictable predicated backedge-taken count. ; CHECK: Loop %for.cond: Unpredictable backedge-taken count. ; CHECK: Loop %for.cond: max backedge-taken count is -2147483647 ; CHECK: Loop %for.cond: Unpredictable predicated backedge-taken count. ; CHECK: Loop %for.cond.outer: Unpredictable backedge-taken count. ; CHECK: Loop %for.cond.outer: Unpredictable max backedge-taken count. ; CHECK: Loop %for.cond.outer: Unpredictable predicated backedge-taken count. define i32 @test() nounwind { entry: br label %for.cond for.cond: ; preds = %if.then5, %if.end, %entry %cuts.1 = phi i32 [ 0, %entry ], [ %inc, %if.then5 ], [ %cuts.1, %if.end ] %0 = phi i32 [ 0, %entry ], [ %add, %if.end ], [ %add, %if.then5 ] %add = add i32 %0, 1 %cmp = icmp slt i32 %0, 1 %tmp1 = load i32, i32* @maxStat, align 4 br i1 %cmp, label %for.body, label %for.cond14.preheader for.cond14.preheader: ; preds = %for.cond %cmp1726 = icmp sgt i32 %tmp1, 0 br i1 %cmp1726, label %for.body18, label %return for.body: ; preds = %for.cond %cmp2 = icmp sgt i32 %tmp1, 100 br i1 %cmp2, label %return, label %if.end if.end: ; preds = %for.body %cmp4 = icmp sgt i32 %tmp1, -1 br i1 %cmp4, label %if.then5, label %for.cond if.then5: ; preds = %if.end call void @foo() nounwind %inc = add i32 %cuts.1, 1 br label %for.cond for.body18: ; preds = %for.body18, %for.cond14.preheader %i13.027 = phi i32 [ %1, %for.body18 ], [ 0, %for.cond14.preheader ] call void @foo() nounwind %1 = add nsw i32 %i13.027, 1 %tmp16 = load i32, i32* @maxStat, align 4 %cmp17 = icmp slt i32 %1, %tmp16 br i1 %cmp17, label %for.body18, label %return return: ; preds = %for.body18, %for.body, %for.cond14.preheader ret i32 0 } declare void @foo() nounwind ; Notify SCEV when removing an ExitingBlock. This only changes the ; backedge-taken information. ; ; First SCEV print: ; CHECK-LABEL: Determining loop execution counts for: @mergeExit ; CHECK: Loop %while.cond191: Unpredictable backedge-taken count. ; CHECK: Loop %while.cond191: max backedge-taken count is -1 ; CHECK: Loop %while.cond191: Unpredictable predicated backedge-taken count. ; CHECK: Loop %while.cond191.outer: Unpredictable backedge-taken count. ; CHECK: Loop %while.cond191.outer: Unpredictable max backedge-taken count. ; CHECK: Loop %while.cond191.outer: Unpredictable predicated backedge-taken count. ; ; After simplifying, the max backedge count is refined. ; Second SCEV print: ; CHECK-LABEL: Determining loop execution counts for: @mergeExit ; CHECK: Loop %while.cond191: backedge-taken count is 0 ; CHECK: Loop %while.cond191: max backedge-taken count is 0 ; CHECK: Loop %while.cond191: Predicated backedge-taken count is 0 ; CHECK: Loop %while.cond191.outer: Unpredictable backedge-taken count. ; CHECK: Loop %while.cond191.outer: max backedge-taken count is false ; CHECK: Loop %while.cond191.outer: Unpredictable predicated backedge-taken count. define void @mergeExit(i32 %MapAttrCount) nounwind uwtable ssp { entry: br i1 undef, label %if.then124, label %if.end126 if.then124: ; preds = %entry unreachable if.end126: ; preds = %entry br i1 undef, label %while.body.lr.ph, label %if.end591 while.body.lr.ph: ; preds = %if.end126 br i1 undef, label %if.end140, label %if.then137 if.then137: ; preds = %while.body.lr.ph unreachable if.end140: ; preds = %while.body.lr.ph br i1 undef, label %while.cond191.outer, label %if.then148 if.then148: ; preds = %if.end140 unreachable while.cond191.outer: ; preds = %if.then205, %if.end140 br label %while.cond191 while.cond191: ; preds = %while.body197, %while.cond191.outer %CppIndex.0 = phi i32 [ %inc, %while.body197 ], [ undef, %while.cond191.outer ] br i1 undef, label %land.rhs, label %if.then216 land.rhs: ; preds = %while.cond191 %inc = add i32 %CppIndex.0, 1 %cmp196 = icmp ult i32 %inc, %MapAttrCount br i1 %cmp196, label %while.body197, label %if.then216 while.body197: ; preds = %land.rhs br i1 undef, label %if.then205, label %while.cond191 if.then205: ; preds = %while.body197 br label %while.cond191.outer if.then216: ; preds = %land.rhs, %while.cond191 br i1 undef, label %if.else, label %if.then221 if.then221: ; preds = %if.then216 unreachable if.else: ; preds = %if.then216 br i1 undef, label %if.then266, label %if.end340 if.then266: ; preds = %if.else switch i32 undef, label %if.else329 [ i32 17, label %if.then285 i32 19, label %if.then285 i32 18, label %if.then285 i32 15, label %if.then285 ] if.then285: ; preds = %if.then266, %if.then266, %if.then266, %if.then266 br i1 undef, label %if.then317, label %if.else324 if.then317: ; preds = %if.then285 br label %if.end340 if.else324: ; preds = %if.then285 unreachable if.else329: ; preds = %if.then266 unreachable if.end340: ; preds = %if.then317, %if.else unreachable if.end591: ; preds = %if.end126 br i1 undef, label %cond.end, label %cond.false cond.false: ; preds = %if.end591 unreachable cond.end: ; preds = %if.end591 ret void }