1 ; RUN: opt < %s -S -loop-unroll -unroll-max-iteration-count-to-analyze=1000 -unroll-threshold=10 -unroll-percent-dynamic-cost-saved-threshold=50 -unroll-dynamic-cost-savings-discount=90 | FileCheck %s 2 target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128" 3 4 @unknown_global = internal unnamed_addr global [9 x i32] [i32 0, i32 -1, i32 0, i32 -1, i32 5, i32 -1, i32 0, i32 -1, i32 0], align 16 5 @weak_constant = weak unnamed_addr constant [9 x i32] [i32 0, i32 -1, i32 0, i32 -1, i32 5, i32 -1, i32 0, i32 -1, i32 0], align 16 6 7 ; Though @unknown_global is initialized with constant values, we can't consider 8 ; it as a constant, so we shouldn't unroll the loop. 9 ; CHECK-LABEL: @foo 10 ; CHECK: %array_const_idx = getelementptr inbounds [9 x i32], [9 x i32]* @unknown_global, i64 0, i64 %iv 11 define i32 @foo(i32* noalias nocapture readonly %src) { 12 entry: 13 br label %loop 14 15 loop: ; preds = %loop, %entry 16 %iv = phi i64 [ 0, %entry ], [ %inc, %loop ] 17 %r = phi i32 [ 0, %entry ], [ %add, %loop ] 18 %arrayidx = getelementptr inbounds i32, i32* %src, i64 %iv 19 %src_element = load i32, i32* %arrayidx, align 4 20 %array_const_idx = getelementptr inbounds [9 x i32], [9 x i32]* @unknown_global, i64 0, i64 %iv 21 %const_array_element = load i32, i32* %array_const_idx, align 4 22 %mul = mul nsw i32 %src_element, %const_array_element 23 %add = add nsw i32 %mul, %r 24 %inc = add nuw nsw i64 %iv, 1 25 %exitcond86.i = icmp eq i64 %inc, 9 26 br i1 %exitcond86.i, label %loop.end, label %loop 27 28 loop.end: ; preds = %loop 29 %r.lcssa = phi i32 [ %r, %loop ] 30 ret i32 %r.lcssa 31 } 32 33 ; Similarly, we can't consider 'weak' symbols as a known constant value, so we 34 ; shouldn't unroll the loop. 35 ; CHECK-LABEL: @foo2 36 ; CHECK: %array_const_idx = getelementptr inbounds [9 x i32], [9 x i32]* @weak_constant, i64 0, i64 %iv 37 define i32 @foo2(i32* noalias nocapture readonly %src) { 38 entry: 39 br label %loop 40 41 loop: ; preds = %loop, %entry 42 %iv = phi i64 [ 0, %entry ], [ %inc, %loop ] 43 %r = phi i32 [ 0, %entry ], [ %add, %loop ] 44 %arrayidx = getelementptr inbounds i32, i32* %src, i64 %iv 45 %src_element = load i32, i32* %arrayidx, align 4 46 %array_const_idx = getelementptr inbounds [9 x i32], [9 x i32]* @weak_constant, i64 0, i64 %iv 47 %const_array_element = load i32, i32* %array_const_idx, align 4 48 %mul = mul nsw i32 %src_element, %const_array_element 49 %add = add nsw i32 %mul, %r 50 %inc = add nuw nsw i64 %iv, 1 51 %exitcond86.i = icmp eq i64 %inc, 9 52 br i1 %exitcond86.i, label %loop.end, label %loop 53 54 loop.end: ; preds = %loop 55 %r.lcssa = phi i32 [ %r, %loop ] 56 ret i32 %r.lcssa 57 } 58
