Index: llvm/lib/Target/ARM/ARMTargetTransformInfo.cpp =================================================================== --- llvm/lib/Target/ARM/ARMTargetTransformInfo.cpp +++ llvm/lib/Target/ARM/ARMTargetTransformInfo.cpp @@ -362,8 +362,12 @@ // Ensures negative constant of min(max()) or max(min()) patterns that // match to SSAT instructions don't get hoisted if (Inst && ((ST->hasV6Ops() && !ST->isThumb()) || ST->isThumb2()) && - Ty->getIntegerBitWidth() <= 32 && isSSATMinMaxPattern(Inst, Imm)) - return 0; + Ty->getIntegerBitWidth() <= 32) { + if (isSSATMinMaxPattern(Inst, Imm) || + (isa(Inst) && Inst->hasOneUse() && + isSSATMinMaxPattern(cast(*Inst->user_begin()), Imm))) + return 0; + } return getIntImmCost(Imm, Ty, CostKind); } Index: llvm/test/CodeGen/ARM/ssat-unroll-loops.ll =================================================================== --- /dev/null +++ llvm/test/CodeGen/ARM/ssat-unroll-loops.ll @@ -0,0 +1,123 @@ +; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py +; RUN: llc -mtriple=armv6t2-eabi %s -o - | FileCheck %s --check-prefix=CHECK + +; Checks SSAT is still generated when loop unrolling is on + +define void @ssat_unroll(i16* %pSrcA, i16* %pSrcB, i16* %pDst, i32 %blockSize) { +; CHECK-LABEL: ssat_unroll: +; CHECK: @ %bb.0: @ %entry +; CHECK-NEXT: .save {r11, lr} +; CHECK-NEXT: push {r11, lr} +; CHECK-NEXT: cmp r3, #0 +; CHECK-NEXT: beq .LBB0_5 +; CHECK-NEXT: @ %bb.1: @ %while.body.preheader +; CHECK-NEXT: sub r12, r3, #1 +; CHECK-NEXT: tst r3, #1 +; CHECK-NEXT: beq .LBB0_3 +; CHECK-NEXT: @ %bb.2: @ %while.body.prol.preheader +; CHECK-NEXT: ldrsh lr, [r0], #2 +; CHECK-NEXT: ldrsh r3, [r1], #2 +; CHECK-NEXT: smulbb r3, r3, lr +; CHECK-NEXT: ssat r3, #16, r3, asr #14 +; CHECK-NEXT: strh r3, [r2], #2 +; CHECK-NEXT: mov r3, r12 +; CHECK-NEXT: .LBB0_3: @ %while.body.prol.loopexit +; CHECK-NEXT: cmp r12, #0 +; CHECK-NEXT: popeq {r11, pc} +; CHECK-NEXT: .LBB0_4: @ %while.body +; CHECK-NEXT: @ =>This Inner Loop Header: Depth=1 +; CHECK-NEXT: ldrsh r12, [r0] +; CHECK-NEXT: subs r3, r3, #2 +; CHECK-NEXT: ldrsh lr, [r1] +; CHECK-NEXT: smulbb r12, lr, r12 +; CHECK-NEXT: ssat r12, #16, r12, asr #14 +; CHECK-NEXT: strh r12, [r2] +; CHECK-NEXT: ldrsh r12, [r0, #2] +; CHECK-NEXT: add r0, r0, #4 +; CHECK-NEXT: ldrsh lr, [r1, #2] +; CHECK-NEXT: add r1, r1, #4 +; CHECK-NEXT: smulbb r12, lr, r12 +; CHECK-NEXT: ssat r12, #16, r12, asr #14 +; CHECK-NEXT: strh r12, [r2, #2] +; CHECK-NEXT: add r2, r2, #4 +; CHECK-NEXT: bne .LBB0_4 +; CHECK-NEXT: .LBB0_5: @ %while.end +; CHECK-NEXT: pop {r11, pc} +entry: + %cmp.not7 = icmp eq i32 %blockSize, 0 + br i1 %cmp.not7, label %while.end, label %while.body.preheader + +while.body.preheader: ; preds = %entry + %0 = add i32 %blockSize, -1 + %xtraiter = and i32 %blockSize, 1 + %lcmp.mod.not = icmp eq i32 %xtraiter, 0 + br i1 %lcmp.mod.not, label %while.body.prol.loopexit, label %while.body.prol.preheader + +while.body.prol.preheader: ; preds = %while.body.preheader + %incdec.ptr.prol = getelementptr inbounds i16, i16* %pSrcA, i32 1 + %1 = load i16, i16* %pSrcA + %conv.prol = sext i16 %1 to i32 + %incdec.ptr1.prol = getelementptr inbounds i16, i16* %pSrcB, i32 1 + %2 = load i16, i16* %pSrcB + %conv2.prol = sext i16 %2 to i32 + %mul.prol = mul nsw i32 %conv2.prol, %conv.prol + %shr.prol = ashr i32 %mul.prol, 14 + %3 = icmp sgt i32 %shr.prol, -32768 + %4 = select i1 %3, i32 %shr.prol, i32 -32768 + %5 = icmp slt i32 %4, 32767 + %spec.select.i.prol = select i1 %5, i32 %4, i32 32767 + %conv3.prol = trunc i32 %spec.select.i.prol to i16 + %incdec.ptr4.prol = getelementptr inbounds i16, i16* %pDst, i32 1 + store i16 %conv3.prol, i16* %pDst + br label %while.body.prol.loopexit + +while.body.prol.loopexit: ; preds = %while.body.prol.preheader, %while.body.preheader + %blkCnt.011.unr = phi i32 [ %blockSize, %while.body.preheader ], [ %0, %while.body.prol.preheader ] + %pSrcA.addr.010.unr = phi i16* [ %pSrcA, %while.body.preheader ], [ %incdec.ptr.prol, %while.body.prol.preheader ] + %pDst.addr.09.unr = phi i16* [ %pDst, %while.body.preheader ], [ %incdec.ptr4.prol, %while.body.prol.preheader ] + %pSrcB.addr.08.unr = phi i16* [ %pSrcB, %while.body.preheader ], [ %incdec.ptr1.prol, %while.body.prol.preheader ] + %6 = icmp eq i32 %0, 0 + br i1 %6, label %while.end, label %while.body + +while.body: ; preds = %while.body.prol.loopexit, %while.body + %blkCnt.011 = phi i32 [ %dec.1, %while.body ], [ %blkCnt.011.unr, %while.body.prol.loopexit ] + %pSrcA.addr.010 = phi i16* [ %incdec.ptr.1, %while.body ], [ %pSrcA.addr.010.unr, %while.body.prol.loopexit ] + %pDst.addr.09 = phi i16* [ %incdec.ptr4.1, %while.body ], [ %pDst.addr.09.unr, %while.body.prol.loopexit ] + %pSrcB.addr.08 = phi i16* [ %incdec.ptr1.1, %while.body ], [ %pSrcB.addr.08.unr, %while.body.prol.loopexit ] + %incdec.ptr = getelementptr inbounds i16, i16* %pSrcA.addr.010, i32 1 + %7 = load i16, i16* %pSrcA.addr.010 + %conv = sext i16 %7 to i32 + %incdec.ptr1 = getelementptr inbounds i16, i16* %pSrcB.addr.08, i32 1 + %8 = load i16, i16* %pSrcB.addr.08 + %conv2 = sext i16 %8 to i32 + %mul = mul nsw i32 %conv2, %conv + %shr = ashr i32 %mul, 14 + %9 = icmp sgt i32 %shr, -32768 + %10 = select i1 %9, i32 %shr, i32 -32768 + %11 = icmp slt i32 %10, 32767 + %spec.select.i = select i1 %11, i32 %10, i32 32767 + %conv3 = trunc i32 %spec.select.i to i16 + %incdec.ptr4 = getelementptr inbounds i16, i16* %pDst.addr.09, i32 1 + store i16 %conv3, i16* %pDst.addr.09 + %incdec.ptr.1 = getelementptr inbounds i16, i16* %pSrcA.addr.010, i32 2 + %12 = load i16, i16* %incdec.ptr + %conv.1 = sext i16 %12 to i32 + %incdec.ptr1.1 = getelementptr inbounds i16, i16* %pSrcB.addr.08, i32 2 + %13 = load i16, i16* %incdec.ptr1 + %conv2.1 = sext i16 %13 to i32 + %mul.1 = mul nsw i32 %conv2.1, %conv.1 + %shr.1 = ashr i32 %mul.1, 14 + %14 = icmp sgt i32 %shr.1, -32768 + %15 = select i1 %14, i32 %shr.1, i32 -32768 + %16 = icmp slt i32 %15, 32767 + %spec.select.i.1 = select i1 %16, i32 %15, i32 32767 + %conv3.1 = trunc i32 %spec.select.i.1 to i16 + %incdec.ptr4.1 = getelementptr inbounds i16, i16* %pDst.addr.09, i32 2 + store i16 %conv3.1, i16* %incdec.ptr4 + %dec.1 = add i32 %blkCnt.011, -2 + %cmp.not.1 = icmp eq i32 %dec.1, 0 + br i1 %cmp.not.1, label %while.end, label %while.body + +while.end: ; preds = %while.body, %while.body.prol.loopexit, %entry + ret void +}