diff options
Diffstat (limited to 'llvm')
| -rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 5 | ||||
| -rw-r--r-- | llvm/test/CodeGen/ARM/urem-opt-size.ll | 28 |
2 files changed, 29 insertions, 4 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 2931ad276a4..3a67fe4ec9d 100644 --- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -14475,6 +14475,11 @@ SDValue DAGCombiner::SimplifySetCC(EVT VT, SDValue N0, SDValue N1, /// by a magic number. /// Ref: "Hacker's Delight" or "The PowerPC Compiler Writer's Guide". SDValue DAGCombiner::BuildSDIV(SDNode *N) { + // when optimising for minimum size, we don't want to expand a div to a mul + // and a shift. + if (DAG.getMachineFunction().getFunction()->optForMinSize()) + return SDValue(); + ConstantSDNode *C = isConstOrConstSplat(N->getOperand(1)); if (!C) return SDValue(); diff --git a/llvm/test/CodeGen/ARM/urem-opt-size.ll b/llvm/test/CodeGen/ARM/urem-opt-size.ll index 4c9aec10d0f..7f1cd43bc4e 100644 --- a/llvm/test/CodeGen/ARM/urem-opt-size.ll +++ b/llvm/test/CodeGen/ARM/urem-opt-size.ll @@ -1,5 +1,5 @@ -; When optimising for minimum size, we don't want to expand a udiv to a mul -; and a shift sequence. As a result, the urem instruction will not be +; When optimising for minimum size, we don't want to expand a div to a mul +; and a shift sequence. As a result, the urem instruction e.g. will not be ; expanded to a sequence of umull, lsrs, muls and sub instructions, but ; just a call to __aeabi_uidivmod. ; @@ -8,9 +8,29 @@ target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64" target triple = "thumbv7m-arm-none-eabi" -define i32 @foo() local_unnamed_addr #0 { +define i32 @foo1() local_unnamed_addr #0 { entry: -; CHECK-LABEL: foo: +; CHECK-LABEL: foo1: +; CHECK:__aeabi_idiv +; CHECK-NOT: smmul + %call = tail call i32 bitcast (i32 (...)* @GetValue to i32 ()*)() + %div = sdiv i32 %call, 1000000 + ret i32 %div +} + +define i32 @foo2() local_unnamed_addr #0 { +entry: +; CHECK-LABEL: foo2: +; CHECK: __aeabi_uidiv +; CHECK-NOT: umull + %call = tail call i32 bitcast (i32 (...)* @GetValue to i32 ()*)() + %div = udiv i32 %call, 1000000 + ret i32 %div +} + +define i32 @foo3() local_unnamed_addr #0 { +entry: +; CHECK-LABEL: foo3: ; CHECK: __aeabi_uidivmod ; CHECK-NOT: umull %call = tail call i32 bitcast (i32 (...)* @GetValue to i32 ()*)() |
