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| author | Weiming Zhao <weimingz@codeaurora.org> | 2016-01-08 18:43:41 +0000 |
|---|---|---|
| committer | Weiming Zhao <weimingz@codeaurora.org> | 2016-01-08 18:43:41 +0000 |
| commit | 432ca7460b008060245c92e1a4c3ff4cf787e0ce (patch) | |
| tree | 7ca9481989c2624ed80ae3d46a6461fb542ce1d0 /test/CodeGen/ARM/bit-reverse-to-rbit.ll | |
| parent | ad748b70b56cb6a2d74ff4b3bf38dbe24b7d838c (diff) | |
RBIT Instruction only available for ARMv6t2 and above.
Summary:
r255334 matches bit-reverse pattern in InstCombine and generates calls to Instrinsic::bitreverse.
RBIT instruction is only available for ARMv6t2 and above. This patch has the intrinsic expanded during legalization for ARMv4 and ARMv5.
Patch by Z. Zheng <zhaoshiz@codeaurora.org>
Reviewers: apazos, jmolloy, weimingz
Subscribers: aemerson, rengolin, llvm-commits
Differential Revision: http://reviews.llvm.org/D15932
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@257188 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'test/CodeGen/ARM/bit-reverse-to-rbit.ll')
| -rw-r--r-- | test/CodeGen/ARM/bit-reverse-to-rbit.ll | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/test/CodeGen/ARM/bit-reverse-to-rbit.ll b/test/CodeGen/ARM/bit-reverse-to-rbit.ll new file mode 100644 index 00000000000..8482cbf69f2 --- /dev/null +++ b/test/CodeGen/ARM/bit-reverse-to-rbit.ll @@ -0,0 +1,34 @@ +;RUN: opt -instcombine -S < %s | llc -mtriple=armv5e--linux-gnueabi | FileCheck %s +;RUN: opt -instcombine -S < %s | llc -mtriple=thumbv4t--linux-gnueabi | FileCheck %s +;RUN: opt -instcombine -S < %s | llc -mtriple=armv6--linux-gnueabi | FileCheck %s + +;RUN: opt -instcombine -S < %s | llc -mtriple=armv7--linux-gnueabi | FileCheck %s --check-prefix=RBIT +;RUN: opt -instcombine -S < %s | llc -mtriple=thumbv8--linux-gnueabi | FileCheck %s --check-prefix=RBIT + +;CHECK-NOT: rbit +;RBIT: rbit + +define void @byte_reversal(i8* %p, i32 %n) { +entry: + br label %for.cond + +for.cond: ; preds = %for.body, %entry + %i.0 = phi i32 [ 0, %entry ], [ %inc, %for.body ] + %cmp = icmp ult i32 %i.0, %n + br i1 %cmp, label %for.body, label %for.end + +for.body: ; preds = %for.cond + %0 = sext i32 %i.0 to i64 + %arrayidx = getelementptr inbounds i8, i8* %p, i64 %0 + %1 = load i8, i8* %arrayidx, align 1 + %or19 = call i8 @llvm.bitreverse.i8(i8 %1) + store i8 %or19, i8* %arrayidx, align 1 + %inc = add i32 %i.0, 1 + br label %for.cond + +for.end: ; preds = %for.cond + ret void +} + +; Function Attrs: nounwind readnone +declare i8 @llvm.bitreverse.i8(i8) |