50b9ca4dda
After https://github.com/llvm/llvm-project/pull/153643, there may be a BranchOnCond with constant condition in the entry block. Simplify those in removeBranchOnConst. This removes a number of redundant conditional branch from entry blocks. In some cases, it may also make the original scalar loop unreachable, because we know it will never execute. In that case, we need to remove the loop from LoopInfo, because all unreachable blocks may dominate each other, making LoopInfo invalid. In those cases, we can also completely remove the loop, for which I'll share a follow-up patch. Depends on https://github.com/llvm/llvm-project/pull/153643. PR: https://github.com/llvm/llvm-project/pull/154510
99 lines
5.5 KiB
LLVM
99 lines
5.5 KiB
LLVM
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
|
|
; RUN: opt -passes=loop-vectorize -mtriple=s390x-ibm-linux -mcpu=z13 -force-vector-width=2 -S %s | FileCheck %s
|
|
|
|
; Test case from PR44020.
|
|
|
|
; In func_21, %rec forms a first order recurrence and we predicate to avoid
|
|
; scalar iteration overhead for a low trip count loop. Make sure we pick
|
|
; the correct insertion point when fixing first order recurrences.
|
|
|
|
@A = external dso_local global [5 x i32], align 4
|
|
@B = external dso_local global [5 x i32], align 4
|
|
|
|
define void @func_21() {
|
|
; CHECK-LABEL: @func_21(
|
|
; CHECK-NEXT: entry:
|
|
; CHECK-NEXT: br label [[VECTOR_PH:%.*]]
|
|
; CHECK: vector.ph:
|
|
; CHECK-NEXT: br label [[VECTOR_BODY:%.*]]
|
|
; CHECK: vector.body:
|
|
; CHECK-NEXT: [[INDEX:%.*]] = phi i64 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[PRED_STORE_CONTINUE4:%.*]] ]
|
|
; CHECK-NEXT: [[VECTOR_RECUR:%.*]] = phi <2 x i32> [ <i32 poison, i32 0>, [[VECTOR_PH]] ], [ [[TMP12:%.*]], [[PRED_STORE_CONTINUE4]] ]
|
|
; CHECK-NEXT: [[VEC_IND:%.*]] = phi <2 x i8> [ <i8 0, i8 1>, [[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], [[PRED_STORE_CONTINUE4]] ]
|
|
; CHECK-NEXT: [[TMP0:%.*]] = add i64 [[INDEX]], 0
|
|
; CHECK-NEXT: [[TMP1:%.*]] = add i64 [[INDEX]], 1
|
|
; CHECK-NEXT: [[TMP2:%.*]] = icmp ule <2 x i8> [[VEC_IND]], splat (i8 4)
|
|
; CHECK-NEXT: [[TMP3:%.*]] = extractelement <2 x i1> [[TMP2]], i32 0
|
|
; CHECK-NEXT: br i1 [[TMP3]], label [[PRED_LOAD_IF:%.*]], label [[PRED_LOAD_CONTINUE:%.*]]
|
|
; CHECK: pred.load.if:
|
|
; CHECK-NEXT: [[TMP4:%.*]] = getelementptr inbounds [5 x i32], ptr @A, i64 0, i64 [[TMP0]]
|
|
; CHECK-NEXT: [[TMP5:%.*]] = load i32, ptr [[TMP4]], align 4
|
|
; CHECK-NEXT: [[TMP6:%.*]] = insertelement <2 x i32> poison, i32 [[TMP5]], i32 0
|
|
; CHECK-NEXT: br label [[PRED_LOAD_CONTINUE]]
|
|
; CHECK: pred.load.continue:
|
|
; CHECK-NEXT: [[TMP7:%.*]] = phi <2 x i32> [ poison, [[VECTOR_BODY]] ], [ [[TMP6]], [[PRED_LOAD_IF]] ]
|
|
; CHECK-NEXT: [[TMP8:%.*]] = extractelement <2 x i1> [[TMP2]], i32 1
|
|
; CHECK-NEXT: br i1 [[TMP8]], label [[PRED_LOAD_IF1:%.*]], label [[PRED_LOAD_CONTINUE2:%.*]]
|
|
; CHECK: pred.load.if1:
|
|
; CHECK-NEXT: [[TMP9:%.*]] = getelementptr inbounds [5 x i32], ptr @A, i64 0, i64 [[TMP1]]
|
|
; CHECK-NEXT: [[TMP10:%.*]] = load i32, ptr [[TMP9]], align 4
|
|
; CHECK-NEXT: [[TMP11:%.*]] = insertelement <2 x i32> [[TMP7]], i32 [[TMP10]], i32 1
|
|
; CHECK-NEXT: br label [[PRED_LOAD_CONTINUE2]]
|
|
; CHECK: pred.load.continue2:
|
|
; CHECK-NEXT: [[TMP12]] = phi <2 x i32> [ [[TMP7]], [[PRED_LOAD_CONTINUE]] ], [ [[TMP11]], [[PRED_LOAD_IF1]] ]
|
|
; CHECK-NEXT: [[TMP13:%.*]] = shufflevector <2 x i32> [[VECTOR_RECUR]], <2 x i32> [[TMP12]], <2 x i32> <i32 1, i32 2>
|
|
; CHECK-NEXT: [[TMP14:%.*]] = extractelement <2 x i1> [[TMP2]], i32 0
|
|
; CHECK-NEXT: br i1 [[TMP14]], label [[PRED_STORE_IF:%.*]], label [[PRED_STORE_CONTINUE:%.*]]
|
|
; CHECK: pred.store.if:
|
|
; CHECK-NEXT: [[TMP15:%.*]] = getelementptr inbounds [5 x i32], ptr @B, i64 0, i64 [[TMP0]]
|
|
; CHECK-NEXT: [[TMP16:%.*]] = extractelement <2 x i32> [[TMP13]], i32 0
|
|
; CHECK-NEXT: store i32 [[TMP16]], ptr [[TMP15]], align 4
|
|
; CHECK-NEXT: br label [[PRED_STORE_CONTINUE]]
|
|
; CHECK: pred.store.continue:
|
|
; CHECK-NEXT: [[TMP17:%.*]] = extractelement <2 x i1> [[TMP2]], i32 1
|
|
; CHECK-NEXT: br i1 [[TMP17]], label [[PRED_STORE_IF3:%.*]], label [[PRED_STORE_CONTINUE4]]
|
|
; CHECK: pred.store.if3:
|
|
; CHECK-NEXT: [[TMP18:%.*]] = getelementptr inbounds [5 x i32], ptr @B, i64 0, i64 [[TMP1]]
|
|
; CHECK-NEXT: [[TMP19:%.*]] = extractelement <2 x i32> [[TMP13]], i32 1
|
|
; CHECK-NEXT: store i32 [[TMP19]], ptr [[TMP18]], align 4
|
|
; CHECK-NEXT: br label [[PRED_STORE_CONTINUE4]]
|
|
; CHECK: pred.store.continue4:
|
|
; CHECK-NEXT: [[INDEX_NEXT]] = add nuw i64 [[INDEX]], 2
|
|
; CHECK-NEXT: [[VEC_IND_NEXT]] = add <2 x i8> [[VEC_IND]], splat (i8 2)
|
|
; CHECK-NEXT: [[TMP20:%.*]] = icmp eq i64 [[INDEX_NEXT]], 6
|
|
; CHECK-NEXT: br i1 [[TMP20]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
|
|
; CHECK: middle.block:
|
|
; CHECK-NEXT: br label [[EXIT:%.*]]
|
|
; CHECK: scalar.ph:
|
|
; CHECK-NEXT: br label [[LOOP:%.*]]
|
|
; CHECK: loop:
|
|
; CHECK-NEXT: [[SCALAR_RECUR:%.*]] = phi i32 [ 0, [[SCALAR_PH:%.*]] ], [ [[LV:%.*]], [[LOOP]] ]
|
|
; CHECK-NEXT: [[INDVARS_IV:%.*]] = phi i64 [ 0, [[SCALAR_PH]] ], [ [[INDVARS_IV_NEXT:%.*]], [[LOOP]] ]
|
|
; CHECK-NEXT: [[A_PTR:%.*]] = getelementptr inbounds [5 x i32], ptr @A, i64 0, i64 [[INDVARS_IV]]
|
|
; CHECK-NEXT: [[LV]] = load i32, ptr [[A_PTR]], align 4
|
|
; CHECK-NEXT: [[B_PTR:%.*]] = getelementptr inbounds [5 x i32], ptr @B, i64 0, i64 [[INDVARS_IV]]
|
|
; CHECK-NEXT: store i32 [[SCALAR_RECUR]], ptr [[B_PTR]], align 4
|
|
; CHECK-NEXT: [[INDVARS_IV_NEXT]] = add nuw nsw i64 [[INDVARS_IV]], 1
|
|
; CHECK-NEXT: [[EXITCOND:%.*]] = icmp eq i64 [[INDVARS_IV_NEXT]], 5
|
|
; CHECK-NEXT: br i1 [[EXITCOND]], label [[EXIT]], label [[LOOP]]
|
|
; CHECK: exit:
|
|
; CHECK-NEXT: ret void
|
|
;
|
|
entry:
|
|
br label %loop
|
|
|
|
loop: ; preds = %loop, %entry
|
|
%rec = phi i32 [ 0, %entry], [ %lv, %loop ]
|
|
%indvars.iv = phi i64 [ 0, %entry], [ %indvars.iv.next, %loop ]
|
|
%A.ptr= getelementptr inbounds [5 x i32], ptr @A, i64 0, i64 %indvars.iv
|
|
%lv = load i32, ptr %A.ptr, align 4
|
|
%B.ptr = getelementptr inbounds [5 x i32], ptr @B, i64 0, i64 %indvars.iv
|
|
store i32 %rec, ptr %B.ptr, align 4
|
|
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
|
|
%exitcond = icmp eq i64 %indvars.iv.next, 5
|
|
br i1 %exitcond, label %exit, label %loop
|
|
|
|
exit: ; preds = %loop
|
|
ret void
|
|
}
|