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 11 define signext i32 @testTripCount2(i32 signext %a) { 12 13 ; CHECK-LABEL: testTripCount2: 14 ; CHECK-NOT: mtctr 15 ; CHECK: blr 16 17 entry: 18 br label %for.body 19 20 for.cond.cleanup: ; preds = %for.body 21 ret i32 %add 22 23 for.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 35 define signext i32 @testTripCount3(i32 signext %a) { 36 37 ; CHECK-LABEL: testTripCount3: 38 ; CHECK-NOT: mtctr 39 ; CHECK: blr 40 41 entry: 42 br label %for.body 43 44 for.cond.cleanup: ; preds = %for.body 45 ret i32 %add 46 47 for.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 60 define signext i32 @testTripCount4(i32 signext %a) { 61 62 ; CHECK-LABEL: testTripCount4: 63 ; CHECK: mtctr 64 ; CHECK: bdnz 65 66 entry: 67 br label %for.body 68 69 for.cond.cleanup: ; preds = %for.body 70 ret i32 %add 71 72 for.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 84 define signext i32 @testTripCount2NonSmallLoop() { 85 86 ; CHECK-LABEL: testTripCount2NonSmallLoop: 87 ; CHECK: mtctr 88 ; CHECK: blr 89 90 entry: 91 %.pre = load i32, i32* @a, align 4 92 br label %for.body 93 94 for.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 100 101 if.then: ; preds = %for.body 102 store i32 2, i32* @a, align 4 103 br label %if.end 104 105 if.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 111 112 for.end: ; preds = %if.end 113 %conv = zext i8 %b.1 to i32 114 ret i32 %conv 115 } 116 117
