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| author | Benjamin Kramer <benny.kra@googlemail.com> | 2013-09-20 14:38:44 +0000 |
|---|---|---|
| committer | Benjamin Kramer <benny.kra@googlemail.com> | 2013-09-20 14:38:44 +0000 |
| commit | 4c332fa5a5a650cd779935d78b505f84cef4db69 (patch) | |
| tree | 5214ed46cdcf9af5d90465acdd5109568517810d /test | |
| parent | 86075251108afff556420effa670e7d07b203555 (diff) | |
| download | external_llvm-4c332fa5a5a650cd779935d78b505f84cef4db69.zip external_llvm-4c332fa5a5a650cd779935d78b505f84cef4db69.tar.gz external_llvm-4c332fa5a5a650cd779935d78b505f84cef4db69.tar.bz2 | |
InstCombine: Canonicalize (gep i8* X, -(ptrtoint Y)) to (sub (ptrtoint X), (ptrtoint Y))
The GEP pattern is what SCEV expander emits for "ugly geps". The latter is what
you get for pointer subtraction in C code. The rest of instcombine already
knows how to deal with that so just canonicalize on that.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191090 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'test')
| -rw-r--r-- | test/Transforms/InstCombine/getelementptr.ll | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/test/Transforms/InstCombine/getelementptr.ll b/test/Transforms/InstCombine/getelementptr.ll index ff8ad63..191a151 100644 --- a/test/Transforms/InstCombine/getelementptr.ll +++ b/test/Transforms/InstCombine/getelementptr.ll @@ -762,4 +762,18 @@ define i8 @test_gep_bitcast_array_different_size_element_as1([100 x double] addr ret i8 %x } +define i64 @test40() { + %array = alloca [3 x i32], align 4 + %gep = getelementptr inbounds [3 x i32]* %array, i64 0, i64 2 + %gepi8 = bitcast i32* %gep to i8* + %p = ptrtoint [3 x i32]* %array to i64 + %np = sub i64 0, %p + %gep2 = getelementptr i8* %gepi8, i64 %np + %ret = ptrtoint i8* %gep2 to i64 + ret i64 %ret + +; CHECK-LABEL: @test40 +; CHECK-NEXT: ret i64 8 +} + ; CHECK: attributes [[NUW]] = { nounwind } |