llvm-capstone/llvm/test/Analysis/MemorySSA/loop-rotate-disablebasicaa.ll
Alina Sbirlea 6b2d1346d8 [MemorySSA] Update MSSA for non-conventional AA.
Summary:
Regularly when moving an instruction that may not read or write memory,
the instruction is not modelled in MSSA, so not action is necessary.
For a non-conventional AA pipeline, MSSA needs to explicitly check when
creating accesses, so as to not model instructions that may not read and
write memory.

Reviewers: george.burgess.iv

Subscribers: Prazek, sanjoy.google, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67562

llvm-svn: 372137
2019-09-17 16:31:37 +00:00

27 lines
799 B
LLVM

; RUN: opt -disable-basicaa -print-memoryssa -disable-output %s 2>&1 | FileCheck %s
; Note: if @foo is modelled as a MemoryDef, this test will assert with -loop-rotate, due to MemorySSA not
; being preserved when moving instructions that may not read from or write to memory.
; CHECK-LABEL: @main
; CHECK-NOT: MemoryDef
define void @main() {
entry:
br label %for.cond120
for.cond120: ; preds = %for.body127, %entry
call void @foo()
br i1 undef, label %for.body127, label %for.cond.cleanup126
for.cond.cleanup126: ; preds = %for.cond120
unreachable
for.body127: ; preds = %for.cond120
%0 = load i16**, i16*** undef, align 1
br label %for.cond120
}
declare void @foo() readnone