diff options
Diffstat (limited to 'llvm/test/Transforms/PhaseOrdering/rotate.ll')
| -rw-r--r-- | llvm/test/Transforms/PhaseOrdering/rotate.ll | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/llvm/test/Transforms/PhaseOrdering/rotate.ll b/llvm/test/Transforms/PhaseOrdering/rotate.ll new file mode 100644 index 00000000000..e10a46cb830 --- /dev/null +++ b/llvm/test/Transforms/PhaseOrdering/rotate.ll @@ -0,0 +1,38 @@ +; NOTE: Assertions have been autogenerated by utils/update_test_checks.py +; RUN: opt -O3 -S < %s | FileCheck %s --check-prefixes=ANY,OLDPM +; RUN: opt -passes='default<O3>' -S < %s | FileCheck %s --check-prefixes=ANY,NEWPM + +; This should become a single funnel shift through a combination +; of aggressive-instcombine, simplifycfg, and instcombine. +; https://bugs.llvm.org/show_bug.cgi?id=34924 +; These are equivalent, but the value name with the new-pm shows a bug - +; this code should not have been converted to a speculative select with +; an intermediate transform. + +define i32 @rotl(i32 %a, i32 %b) { +; OLDPM-LABEL: @rotl( +; OLDPM-NEXT: entry: +; OLDPM-NEXT: [[TMP0:%.*]] = tail call i32 @llvm.fshl.i32(i32 [[A:%.*]], i32 [[A]], i32 [[B:%.*]]) +; OLDPM-NEXT: ret i32 [[TMP0]] +; +; NEWPM-LABEL: @rotl( +; NEWPM-NEXT: entry: +; NEWPM-NEXT: [[SPEC_SELECT:%.*]] = tail call i32 @llvm.fshl.i32(i32 [[A:%.*]], i32 [[A]], i32 [[B:%.*]]) +; NEWPM-NEXT: ret i32 [[SPEC_SELECT]] +; +entry: + %cmp = icmp eq i32 %b, 0 + br i1 %cmp, label %end, label %rotbb + +rotbb: + %sub = sub i32 32, %b + %shr = lshr i32 %a, %sub + %shl = shl i32 %a, %b + %or = or i32 %shr, %shl + br label %end + +end: + %cond = phi i32 [ %or, %rotbb ], [ %a, %entry ] + ret i32 %cond +} + |
