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
61 lines
2.7 KiB
LLVM
61 lines
2.7 KiB
LLVM
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals none --version 5
|
|
; RUN: opt -p loop-vectorize -force-vector-interleave=1 -force-vector-width=4 -S < %s | FileCheck %s
|
|
|
|
define void @neg_cond(ptr noalias %p, ptr noalias %q) {
|
|
; CHECK-LABEL: define void @neg_cond(
|
|
; CHECK-SAME: ptr noalias [[P:%.*]], ptr noalias [[Q:%.*]]) {
|
|
; 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 i32 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
|
|
; CHECK-NEXT: [[TMP0:%.*]] = getelementptr i32, ptr [[P]], i32 [[INDEX]]
|
|
; CHECK-NEXT: [[WIDE_LOAD:%.*]] = load <4 x i32>, ptr [[TMP0]], align 4
|
|
; CHECK-NEXT: [[TMP3:%.*]] = icmp ne <4 x i32> [[WIDE_LOAD]], splat (i32 42)
|
|
; CHECK-NEXT: [[TMP4:%.*]] = select <4 x i1> [[TMP3]], <4 x i32> splat (i32 42), <4 x i32> splat (i32 43)
|
|
; CHECK-NEXT: store <4 x i32> [[TMP4]], ptr [[TMP0]], align 4
|
|
; CHECK-NEXT: [[INDEX_NEXT]] = add nuw i32 [[INDEX]], 4
|
|
; CHECK-NEXT: [[TMP5:%.*]] = icmp eq i32 [[INDEX_NEXT]], 1024
|
|
; CHECK-NEXT: br i1 [[TMP5]], 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: [[IV:%.*]] = phi i32 [ 0, %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
|
|
; CHECK-NEXT: [[P_GEP:%.*]] = getelementptr i32, ptr [[P]], i32 [[IV]]
|
|
; CHECK-NEXT: [[X:%.*]] = load i32, ptr [[P_GEP]], align 4
|
|
; CHECK-NEXT: [[Q_GEP:%.*]] = getelementptr i32, ptr [[Q]], i32 [[IV]]
|
|
; CHECK-NEXT: [[Y:%.*]] = load i32, ptr [[Q_GEP]], align 4
|
|
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[X]], 42
|
|
; CHECK-NEXT: [[NOT:%.*]] = xor i1 [[CMP]], true
|
|
; CHECK-NEXT: [[SEL:%.*]] = select i1 [[NOT]], i32 42, i32 43
|
|
; CHECK-NEXT: store i32 [[SEL]], ptr [[P_GEP]], align 4
|
|
; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1
|
|
; CHECK-NEXT: [[DONE:%.*]] = icmp eq i32 [[IV_NEXT]], 1024
|
|
; CHECK-NEXT: br i1 [[DONE]], label %[[EXIT]], label %[[LOOP]]
|
|
; CHECK: [[EXIT]]:
|
|
; CHECK-NEXT: ret void
|
|
;
|
|
entry:
|
|
br label %loop
|
|
|
|
loop:
|
|
%iv = phi i32 [0, %entry], [%iv.next, %loop]
|
|
%p.gep = getelementptr i32, ptr %p, i32 %iv
|
|
%x = load i32, ptr %p.gep
|
|
%q.gep = getelementptr i32, ptr %q, i32 %iv
|
|
%y = load i32, ptr %q.gep
|
|
%cmp = icmp eq i32 %x, 42
|
|
%not = xor i1 %cmp, 1
|
|
%sel = select i1 %not, i32 42, i32 43
|
|
store i32 %sel, ptr %p.gep
|
|
%iv.next = add i32 %iv, 1
|
|
%done = icmp eq i32 %iv.next, 1024
|
|
br i1 %done, label %exit, label %loop
|
|
|
|
exit:
|
|
ret void
|
|
}
|