X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=test%2FTransforms%2FLoopUnroll%2Fscevunroll.ll;h=a5c9a6efacf38fdcad66c97144ff5ff3040e2b32;hb=6cd07b45e172b457428b291fa28252e507a7c50c;hp=99b3a7d861971e323f6c8ae3da5f21f6316f1d3e;hpb=b0598b14aa011a18e6a760e448741f62018fb4a3;p=oota-llvm.git diff --git a/test/Transforms/LoopUnroll/scevunroll.ll b/test/Transforms/LoopUnroll/scevunroll.ll index 99b3a7d8619..a5c9a6efacf 100644 --- a/test/Transforms/LoopUnroll/scevunroll.ll +++ b/test/Transforms/LoopUnroll/scevunroll.ll @@ -7,7 +7,7 @@ ; Completely unroll loops without a canonical IV. ; -; CHECK: @sansCanonical +; CHECK-LABEL: @sansCanonical( ; CHECK-NOT: phi ; CHECK-NOT: icmp ; CHECK: ret @@ -19,8 +19,8 @@ while.body: %iv = phi i64 [ 10, %entry ], [ %iv.next, %while.body ] %sum = phi i32 [ 0, %entry ], [ %sum.next, %while.body ] %iv.next = add i64 %iv, -1 - %adr = getelementptr inbounds i32* %base, i64 %iv.next - %tmp = load i32* %adr, align 8 + %adr = getelementptr inbounds i32, i32* %base, i64 %iv.next + %tmp = load i32, i32* %adr, align 8 %sum.next = add i32 %sum, %tmp %iv.narrow = trunc i64 %iv.next to i32 %cmp.i65 = icmp sgt i32 %iv.narrow, 0 @@ -35,7 +35,7 @@ exit: ; latch block. Canonical unrolling incorrectly unrolls it, but SCEV ; unrolling does not. ; -; CHECK: @earlyLoopTest +; CHECK-LABEL: @earlyLoopTest( ; CHECK: tail: ; CHECK-NOT: br ; CHECK: br i1 %cmp2, label %loop, label %exit2 @@ -46,8 +46,8 @@ entry: loop: %iv = phi i64 [ 0, %entry ], [ %inc, %tail ] %s = phi i64 [ 0, %entry ], [ %s.next, %tail ] - %adr = getelementptr i64* %base, i64 %iv - %val = load i64* %adr + %adr = getelementptr i64, i64* %base, i64 %iv + %val = load i64, i64* %adr %s.next = add i64 %s, %val %inc = add i64 %iv, 1 %cmp = icmp ne i64 %inc, 4 @@ -66,9 +66,9 @@ exit2: ; SCEV properly unrolls multi-exit loops. ; -; CHECK: @multiExit -; CHECK: getelementptr i32* %base, i32 10 -; CHECK-NEXT: load i32* +; CHECK-LABEL: @multiExit( +; CHECK: getelementptr i32, i32* %base, i32 10 +; CHECK-NEXT: load i32, i32* ; CHECK: br i1 false, label %l2.10, label %exit1 ; CHECK: l2.10: ; CHECK-NOT: br @@ -81,8 +81,8 @@ l1: %iv2 = phi i32 [ 0, %entry ], [ %inc2, %l2 ] %inc1 = add i32 %iv1, 1 %inc2 = add i32 %iv2, 1 - %adr = getelementptr i32* %base, i32 %iv1 - %val = load i32* %adr + %adr = getelementptr i32, i32* %base, i32 %iv1 + %val = load i32, i32* %adr %cmp1 = icmp slt i32 %iv1, 5 br i1 %cmp1, label %l2, label %exit1 l2: @@ -100,7 +100,7 @@ exit2: ; LoopUnroll utility uses this assumption to optimize the latch ; block's branch. ; -; CHECK: @multiExit +; CHECK-LABEL: @multiExitIncomplete( ; CHECK: l3: ; CHECK-NOT: br ; CHECK: br i1 %cmp3, label %l1, label %exit3 @@ -112,8 +112,8 @@ l1: %iv2 = phi i32 [ 0, %entry ], [ %inc2, %l3 ] %inc1 = add i32 %iv1, 1 %inc2 = add i32 %iv2, 1 - %adr = getelementptr i32* %base, i32 %iv1 - %val = load i32* %adr + %adr = getelementptr i32, i32* %base, i32 %iv1 + %val = load i32, i32* %adr %cmp1 = icmp slt i32 %iv1, 5 br i1 %cmp1, label %l2, label %exit1 l2: @@ -134,7 +134,7 @@ exit3: ; When loop unroll merges a loop exit with one of its parent loop's ; exits, SCEV must forget its ExitNotTaken info. ; -; CHECK: @nestedUnroll +; CHECK-LABEL: @nestedUnroll( ; CHECK-NOT: br i1 ; CHECK: for.body87: define void @nestedUnroll() nounwind { @@ -170,3 +170,38 @@ for.body87: br label %for.body87 } +; PR16130: clang produces incorrect code with loop/expression at -O2 +; rdar:14036816 loop-unroll makes assumptions about undefined behavior +; +; The loop latch is assumed to exit after the first iteration because +; of the induction variable's NSW flag. However, the loop latch's +; equality test is skipped and the loop exits after the second +; iteration via the early exit. So loop unrolling cannot assume that +; the loop latch's exit count of zero is an upper bound on the number +; of iterations. +; +; CHECK-LABEL: @nsw_latch( +; CHECK: for.body: +; CHECK: %b.03 = phi i32 [ 0, %entry ], [ %add, %for.cond ] +; CHECK: return: +; CHECK: %b.03.lcssa = phi i32 [ %b.03, %for.body ], [ %b.03, %for.cond ] +define void @nsw_latch(i32* %a) nounwind { +entry: + br label %for.body + +for.body: ; preds = %for.cond, %entry + %b.03 = phi i32 [ 0, %entry ], [ %add, %for.cond ] + %tobool = icmp eq i32 %b.03, 0 + %add = add nsw i32 %b.03, 8 + br i1 %tobool, label %for.cond, label %return + +for.cond: ; preds = %for.body + %cmp = icmp eq i32 %add, 13 + br i1 %cmp, label %return, label %for.body + +return: ; preds = %for.body, %for.cond + %b.03.lcssa = phi i32 [ %b.03, %for.body ], [ %b.03, %for.cond ] + %retval.0 = phi i32 [ 1, %for.body ], [ 0, %for.cond ] + store i32 %b.03.lcssa, i32* %a, align 4 + ret void +}