diff options
| author | Benjamin Kramer <benny.kra@googlemail.com> | 2013-08-30 14:35:35 +0000 |
|---|---|---|
| committer | Benjamin Kramer <benny.kra@googlemail.com> | 2013-08-30 14:35:35 +0000 |
| commit | a8517ee7329636e3b2862784f1abf1f8d892fee7 (patch) | |
| tree | f00c68d7135019a37b6fc335072f443979fa695f /test | |
| parent | d7a178eee39d3caeea8d4354d24daa8b096a1ff2 (diff) | |
| download | external_llvm-a8517ee7329636e3b2862784f1abf1f8d892fee7.zip external_llvm-a8517ee7329636e3b2862784f1abf1f8d892fee7.tar.gz external_llvm-a8517ee7329636e3b2862784f1abf1f8d892fee7.tar.bz2 | |
InstCombine: Check for zero shift amounts before subtracting one causing integer overflow.
PR17026. Also avoid undefined shifts and shift amounts larger than 64 bits
(those are always undef because we can't represent integer types that large).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189672 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'test')
| -rw-r--r-- | test/Transforms/InstCombine/shift.ll | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/test/Transforms/InstCombine/shift.ll b/test/Transforms/InstCombine/shift.ll index 0bdab13..b1082f0 100644 --- a/test/Transforms/InstCombine/shift.ll +++ b/test/Transforms/InstCombine/shift.ll @@ -744,3 +744,39 @@ define i32 @test62(i32 %x) { ; CHECK-LABEL: @test62( ; CHECK: ashr exact i32 %x, 3 } + +; PR17026 +; CHECK-LABEL: @test63( +; CHECK-NOT: sh +; CHECK: ret +define void @test63(i128 %arg) { +bb: + br i1 undef, label %bb1, label %bb12 + +bb1: ; preds = %bb11, %bb + br label %bb2 + +bb2: ; preds = %bb7, %bb1 + br i1 undef, label %bb3, label %bb7 + +bb3: ; preds = %bb2 + %tmp = lshr i128 %arg, 36893488147419103232 + %tmp4 = shl i128 %tmp, 0 + %tmp5 = or i128 %tmp4, undef + %tmp6 = trunc i128 %tmp5 to i16 + br label %bb8 + +bb7: ; preds = %bb2 + br i1 undef, label %bb8, label %bb2 + +bb8: ; preds = %bb7, %bb3 + %tmp9 = phi i16 [ %tmp6, %bb3 ], [ undef, %bb7 ] + %tmp10 = icmp eq i16 %tmp9, 0 + br i1 %tmp10, label %bb11, label %bb12 + +bb11: ; preds = %bb8 + br i1 undef, label %bb1, label %bb12 + +bb12: ; preds = %bb11, %bb8, %bb + ret void +} |