| ; RUN: opt < %s -S -passes=loop-unroll -unroll-max-iteration-count-to-analyze=1000 -unroll-threshold=10 -unroll-max-percent-threshold-boost=200 | FileCheck %s |
| ; RUN: opt < %s -S -passes='require<opt-remark-emit>,loop(loop-unroll-full)' -unroll-max-iteration-count-to-analyze=1000 -unroll-threshold=10 -unroll-max-percent-threshold-boost=200 | FileCheck %s |
| target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128" |
| |
| @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 |
| @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 |
| |
| ; Though @unknown_global is initialized with constant values, we can't consider |
| ; it as a constant, so we shouldn't unroll the loop. |
| ; CHECK-LABEL: @foo |
| ; CHECK: %array_const_idx = getelementptr inbounds [9 x i32], ptr @unknown_global, i64 0, i64 %iv |
| define i32 @foo(ptr noalias nocapture readonly %src) { |
| entry: |
| br label %loop |
| |
| loop: ; preds = %loop, %entry |
| %iv = phi i64 [ 0, %entry ], [ %inc, %loop ] |
| %r = phi i32 [ 0, %entry ], [ %add, %loop ] |
| %arrayidx = getelementptr inbounds i32, ptr %src, i64 %iv |
| %src_element = load i32, ptr %arrayidx, align 4 |
| %array_const_idx = getelementptr inbounds [9 x i32], ptr @unknown_global, i64 0, i64 %iv |
| %const_array_element = load i32, ptr %array_const_idx, align 4 |
| %mul = mul nsw i32 %src_element, %const_array_element |
| %add = add nsw i32 %mul, %r |
| %inc = add nuw nsw i64 %iv, 1 |
| %exitcond86.i = icmp eq i64 %inc, 9 |
| br i1 %exitcond86.i, label %loop.end, label %loop |
| |
| loop.end: ; preds = %loop |
| %r.lcssa = phi i32 [ %r, %loop ] |
| ret i32 %r.lcssa |
| } |
| |
| ; Similarly, we can't consider 'weak' symbols as a known constant value, so we |
| ; shouldn't unroll the loop. |
| ; CHECK-LABEL: @foo2 |
| ; CHECK: %array_const_idx = getelementptr inbounds [9 x i32], ptr @weak_constant, i64 0, i64 %iv |
| define i32 @foo2(ptr noalias nocapture readonly %src) { |
| entry: |
| br label %loop |
| |
| loop: ; preds = %loop, %entry |
| %iv = phi i64 [ 0, %entry ], [ %inc, %loop ] |
| %r = phi i32 [ 0, %entry ], [ %add, %loop ] |
| %arrayidx = getelementptr inbounds i32, ptr %src, i64 %iv |
| %src_element = load i32, ptr %arrayidx, align 4 |
| %array_const_idx = getelementptr inbounds [9 x i32], ptr @weak_constant, i64 0, i64 %iv |
| %const_array_element = load i32, ptr %array_const_idx, align 4 |
| %mul = mul nsw i32 %src_element, %const_array_element |
| %add = add nsw i32 %mul, %r |
| %inc = add nuw nsw i64 %iv, 1 |
| %exitcond86.i = icmp eq i64 %inc, 9 |
| br i1 %exitcond86.i, label %loop.end, label %loop |
| |
| loop.end: ; preds = %loop |
| %r.lcssa = phi i32 [ %r, %loop ] |
| ret i32 %r.lcssa |
| } |
| |
| ; In this case the loaded value is used only to control branch. |
| ; If we missed that, we could've thought that it's unused and unrolling would |
| ; clean up almost entire loop. Make sure that we do not unroll such loop. |
| ; CHECK-LABEL: @foo3 |
| ; CHECK: br i1 %exitcond, label %loop.end, label %loop.header |
| define i32 @foo3(ptr noalias nocapture readonly %src) { |
| entry: |
| br label %loop.header |
| |
| loop.header: |
| %iv = phi i64 [ 0, %entry ], [ %inc, %loop.latch ] |
| %r1 = phi i32 [ 0, %entry ], [ %r3, %loop.latch ] |
| %arrayidx = getelementptr inbounds i32, ptr %src, i64 %iv |
| %src_element = load i32, ptr %arrayidx, align 4 |
| %cmp = icmp eq i32 0, %src_element |
| br i1 %cmp, label %loop.if, label %loop.latch |
| |
| loop.if: |
| %r2 = add i32 %r1, 1 |
| br label %loop.latch |
| |
| loop.latch: |
| %r3 = phi i32 [%r1, %loop.header], [%r2, %loop.if] |
| %inc = add nuw nsw i64 %iv, 1 |
| %exitcond = icmp eq i64 %inc, 9 |
| br i1 %exitcond, label %loop.end, label %loop.header |
| |
| loop.end: |
| %r.lcssa = phi i32 [ %r3, %loop.latch ] |
| ret i32 %r.lcssa |
| } |