diff options
| author | Chris Lattner <sabre@nondot.org> | 2010-12-19 18:22:06 +0000 |
|---|---|---|
| committer | Chris Lattner <sabre@nondot.org> | 2010-12-19 18:22:06 +0000 |
| commit | dd7e83737491b14ebf98e09fa6cb9b515f9f2e3e (patch) | |
| tree | cdfd1a40046996f8fc5842e43ad4ffdf6d65d38b /test/Transforms/InstCombine | |
| parent | d959da92a5a479c7f8f4ccbf7a7e3fb87f9fda0c (diff) | |
| download | external_llvm-dd7e83737491b14ebf98e09fa6cb9b515f9f2e3e.zip external_llvm-dd7e83737491b14ebf98e09fa6cb9b515f9f2e3e.tar.gz external_llvm-dd7e83737491b14ebf98e09fa6cb9b515f9f2e3e.tar.bz2 | |
fix another miscompile in the llvm.sadd formation logic: it wasn't
checking to see if the high bits of the original add result were dead.
Inserting a smaller add and zexting back to that size is not good enough.
This is likely to be the fix for 8816.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122177 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'test/Transforms/InstCombine')
| -rw-r--r-- | test/Transforms/InstCombine/overflow.ll | 23 |
1 files changed, 22 insertions, 1 deletions
diff --git a/test/Transforms/InstCombine/overflow.ll b/test/Transforms/InstCombine/overflow.ll index e54d315..da20e2c 100644 --- a/test/Transforms/InstCombine/overflow.ll +++ b/test/Transforms/InstCombine/overflow.ll @@ -11,7 +11,7 @@ entry: %conv2 = sext i32 %b to i64 %add = add nsw i64 %conv2, %conv %add.off = add i64 %add, 2147483648 -; CHECK: llvm.sadd.with.overflow +; CHECK: llvm.sadd.with.overflow.i32 %0 = icmp ugt i64 %add.off, 4294967295 br i1 %0, label %if.then, label %if.end @@ -53,3 +53,24 @@ if.end: ret i32 %conv9 } +; CHECK: test3 +; This is illegal to transform because the high bits of the original add are +; live out. +define i64 @test3(i32 %a, i32 %b) nounwind ssp { +entry: + %conv = sext i32 %a to i64 + %conv2 = sext i32 %b to i64 + %add = add nsw i64 %conv2, %conv + %add.off = add i64 %add, 2147483648 +; CHECK-NOT: llvm.sadd.with.overflow + %0 = icmp ugt i64 %add.off, 4294967295 + br i1 %0, label %if.then, label %if.end + +if.then: + %call = tail call i32 (...)* @throwAnExceptionOrWhatever() nounwind + br label %if.end + +if.end: + ret i64 %add +; CHECK: ret i64 +} |