; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt < %s -S -loop-unroll -unroll-threshold=1 | FileCheck %s ; RUN: opt < %s -S -passes='require<opt-remark-emit>,loop(loop-unroll-full)' -unroll-threshold=1 | FileCheck %s target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128" ; Body fully unrolls into a single instruction after unroll and simplify define i32 @test(i8 %a) { ; CHECK-LABEL: @test( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[FOR_BODY:%.*]] ; CHECK: for.body: ; CHECK-NEXT: [[ZEXT_9:%.*]] = zext i8 [[A:%.*]] to i32 ; CHECK-NEXT: ret i32 [[ZEXT_9]] ; entry: br label %for.body for.body: %phi = phi i64 [ 0, %entry ], [ %inc, %for.body ] %zext = zext i8 %a to i32 %inc = add nuw nsw i64 %phi, 1 %cmp = icmp ult i64 %inc, 10 br i1 %cmp, label %for.body, label %for.exit for.exit: ret i32 %zext } ; Generalized version of previous to show benefit of using SCEV's ability ; to prove invariance not Loop::isLoopInvaraint. define i32 @test2(i8 %a) { ; CHECK-LABEL: @test2( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[FOR_BODY:%.*]] ; CHECK: for.body: ; CHECK-NEXT: [[ZEXT_9:%.*]] = zext i8 [[A:%.*]] to i32 ; CHECK-NEXT: [[AND_9:%.*]] = and i32 [[ZEXT_9]], 31 ; CHECK-NEXT: [[SHL_9:%.*]] = shl i32 [[AND_9]], 15 ; CHECK-NEXT: ret i32 [[SHL_9]] ; entry: br label %for.body for.body: %phi = phi i64 [ 0, %entry ], [ %inc, %for.body ] %zext = zext i8 %a to i32 %and = and i32 %zext, 31 %shl = shl i32 %and, 15 %inc = add nuw nsw i64 %phi, 1 %cmp = icmp ult i64 %inc, 10 br i1 %cmp, label %for.body, label %for.exit for.exit: ret i32 %shl } ; Show that this works for instructions which might fault as well define i32 @test3(i8 %a) { ; CHECK-LABEL: @test3( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[FOR_BODY:%.*]] ; CHECK: for.body: ; CHECK-NEXT: [[ZEXT_9:%.*]] = zext i8 [[A:%.*]] to i32 ; CHECK-NEXT: [[DIV_9:%.*]] = udiv i32 [[ZEXT_9]], 31 ; CHECK-NEXT: ret i32 [[DIV_9]] ; entry: br label %for.body for.body: %phi = phi i64 [ 0, %entry ], [ %inc, %for.body ] %zext = zext i8 %a to i32 %div = udiv i32 %zext, 31 %inc = add nuw nsw i64 %phi, 1 %cmp = icmp ult i64 %inc, 10 br i1 %cmp, label %for.body, label %for.exit for.exit: ret i32 %div }