1; RUN: llc < %s -mtriple=powerpc64le-unknown-linux-gnu -verify-machineinstrs -mcpu=pwr8 | FileCheck %s 2; RUN: llc < %s -mtriple=powerpc64le-unknown-linux-gnu -verify-machineinstrs -mcpu=a2q | FileCheck %s 3 4; Verify that we do NOT generate the mtctr instruction for loop trip counts < 4 5; The latency of the mtctr is only justified if there are more than 4 comparisons that are removed as a result. 6 7@a = common local_unnamed_addr global i32 0, align 4 8@arr = common local_unnamed_addr global [5 x i32] zeroinitializer, align 4 9 10; Function Attrs: norecurse nounwind readonly 11define signext i32 @testTripCount2(i32 signext %a) { 12 13; CHECK-LABEL: testTripCount2: 14; CHECK-NOT: mtctr 15; CHECK: blr 16 17entry: 18 br label %for.body 19 20for.cond.cleanup: ; preds = %for.body 21 ret i32 %add 22 23for.body: ; preds = %entry, %for.body 24 %indvars.iv = phi i64 [ 1, %entry ], [ %indvars.iv.next, %for.body ] 25 %Sum.05 = phi i32 [ 0, %entry ], [ %add, %for.body ] 26 %arrayidx = getelementptr inbounds [5 x i32], [5 x i32]* @arr, i64 0, i64 %indvars.iv 27 %0 = load i32, i32* %arrayidx, align 4 28 %add = add nsw i32 %0, %Sum.05 29 %indvars.iv.next = add nsw i64 %indvars.iv, -1 30 %tobool = icmp eq i64 %indvars.iv, 0 31 br i1 %tobool, label %for.cond.cleanup, label %for.body 32} 33 34; Function Attrs: norecurse nounwind readonly 35define signext i32 @testTripCount3(i32 signext %a) { 36 37; CHECK-LABEL: testTripCount3: 38; CHECK-NOT: mtctr 39; CHECK: blr 40 41entry: 42 br label %for.body 43 44for.cond.cleanup: ; preds = %for.body 45 ret i32 %add 46 47for.body: ; preds = %entry, %for.body 48 %indvars.iv = phi i64 [ 2, %entry ], [ %indvars.iv.next, %for.body ] 49 %Sum.05 = phi i32 [ 0, %entry ], [ %add, %for.body ] 50 %arrayidx = getelementptr inbounds [5 x i32], [5 x i32]* @arr, i64 0, i64 %indvars.iv 51 %0 = load i32, i32* %arrayidx, align 4 52 %add = add nsw i32 %0, %Sum.05 53 %indvars.iv.next = add nsw i64 %indvars.iv, -1 54 %tobool = icmp eq i64 %indvars.iv, 0 55 br i1 %tobool, label %for.cond.cleanup, label %for.body 56} 57 58; Function Attrs: norecurse nounwind readonly 59 60define signext i32 @testTripCount4(i32 signext %a) { 61 62; CHECK-LABEL: testTripCount4: 63; CHECK: mtctr 64; CHECK: bdnz 65 66entry: 67 br label %for.body 68 69for.cond.cleanup: ; preds = %for.body 70 ret i32 %add 71 72for.body: ; preds = %entry, %for.body 73 %indvars.iv = phi i64 [ 3, %entry ], [ %indvars.iv.next, %for.body ] 74 %Sum.05 = phi i32 [ 0, %entry ], [ %add, %for.body ] 75 %arrayidx = getelementptr inbounds [5 x i32], [5 x i32]* @arr, i64 0, i64 %indvars.iv 76 %0 = load i32, i32* %arrayidx, align 4 77 %add = add nsw i32 %0, %Sum.05 78 %indvars.iv.next = add nsw i64 %indvars.iv, -1 79 %tobool = icmp eq i64 %indvars.iv, 0 80 br i1 %tobool, label %for.cond.cleanup, label %for.body 81} 82 83; Function Attrs: norecurse nounwind 84define signext i32 @testTripCount2NonSmallLoop() { 85 86; CHECK-LABEL: testTripCount2NonSmallLoop: 87; CHECK: mtctr 88; CHECK: blr 89 90entry: 91 %.pre = load i32, i32* @a, align 4 92 br label %for.body 93 94for.body: ; preds = %entry, %if.end 95 %0 = phi i32 [ %.pre, %entry ], [ %1, %if.end ] 96 %dec4 = phi i32 [ 1, %entry ], [ %dec, %if.end ] 97 %b.03 = phi i8 [ 0, %entry ], [ %b.1, %if.end ] 98 %tobool1 = icmp eq i32 %0, 0 99 br i1 %tobool1, label %if.end, label %if.then 100 101if.then: ; preds = %for.body 102 store i32 2, i32* @a, align 4 103 br label %if.end 104 105if.end: ; preds = %for.body, %if.then 106 %1 = phi i32 [ 2, %if.then ], [ 0, %for.body ] 107 %b.1 = phi i8 [ 2, %if.then ], [ %b.03, %for.body ] 108 %dec = add nsw i32 %dec4, -1 109 %tobool = icmp eq i32 %dec4, 0 110 br i1 %tobool, label %for.end, label %for.body 111 112for.end: ; preds = %if.end 113 %conv = zext i8 %b.1 to i32 114 ret i32 %conv 115} 116 117