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| author | Dan Gohman <gohman@apple.com> | 2009-02-18 17:22:41 +0000 |
|---|---|---|
| committer | Dan Gohman <gohman@apple.com> | 2009-02-18 17:22:41 +0000 |
| commit | f5a309e989b8d2199cb542793e9edf48395d9fed (patch) | |
| tree | c52543300d485f04baebd2bc1ee8f1fb7721a411 /test/Transforms/IndVarSimplify/signed-trip-count.ll | |
| parent | cad24c9abc834db5cf8f92019f99370507d8d07a (diff) | |
| download | external_llvm-f5a309e989b8d2199cb542793e9edf48395d9fed.zip external_llvm-f5a309e989b8d2199cb542793e9edf48395d9fed.tar.gz external_llvm-f5a309e989b8d2199cb542793e9edf48395d9fed.tar.bz2 | |
Use a sign-extend instead of a zero-extend when promoting a
trip count value when the original loop iteration condition is
signed and the canonical induction variable won't undergo signed
overflow. This isn't required for correctness; it just preserves
more information about original loop iteration values.
Add a getTruncateOrSignExtend method to ScalarEvolution,
following getTruncateOrZeroExtend.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64918 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'test/Transforms/IndVarSimplify/signed-trip-count.ll')
| -rw-r--r-- | test/Transforms/IndVarSimplify/signed-trip-count.ll | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/test/Transforms/IndVarSimplify/signed-trip-count.ll b/test/Transforms/IndVarSimplify/signed-trip-count.ll new file mode 100644 index 0000000..cea9f82 --- /dev/null +++ b/test/Transforms/IndVarSimplify/signed-trip-count.ll @@ -0,0 +1,31 @@ +; RUN: llvm-as < %s | opt -indvars | llvm-dis > %t +; RUN: grep { = sext i32 %n} %t +; RUN: grep phi %t | count 1 +; RUN: not grep zext %t + +define void @foo(i64* nocapture %x, i32 %n) nounwind { +entry: + %tmp102 = icmp sgt i32 %n, 0 ; <i1> [#uses=1] + br i1 %tmp102, label %bb.nph, label %return + +bb.nph: ; preds = %entry + br label %bb + +bb: ; preds = %bb7, %bb.nph + %i.01 = phi i32 [ %tmp6, %bb7 ], [ 0, %bb.nph ] ; <i32> [#uses=3] + %tmp1 = sext i32 %i.01 to i64 ; <i64> [#uses=1] + %tmp4 = getelementptr i64* %x, i32 %i.01 ; <i64*> [#uses=1] + store i64 %tmp1, i64* %tmp4, align 8 + %tmp6 = add i32 %i.01, 1 ; <i32> [#uses=2] + br label %bb7 + +bb7: ; preds = %bb + %tmp10 = icmp slt i32 %tmp6, %n ; <i1> [#uses=1] + br i1 %tmp10, label %bb, label %bb7.return_crit_edge + +bb7.return_crit_edge: ; preds = %bb7 + br label %return + +return: ; preds = %bb7.return_crit_edge, %entry + ret void +} |