[LoopVersioningLICM] Only mark pointers with generated checks as noalias (#135168)
Currently when we version a loop all loads and stores have the noalias
metadata added to them. If there were some pointers that could not be
analysed, and thus we could not generate runtime aliasing checks for,
then we should not mark loads and stores using these pointers as
noalias.
This is done by getting rid of setNoAliasToLoop and instead using
annotateLoopWithNoAlias, as that already correctly handles partial alias
information. This does result in slightly different aliasing metadata
being generated, but it looks like it's more precise.
Currently this doesn't result in any change to the transforms that
LoopVersioningLICM does, as LoopAccessAnalysis discards all results if
it couldn't analyse every pointer leading to no loop versioning
happening, but an upcoming patch will change that and we need this first
otherwise we incorrectly mark some pointers as noalias even when they
aren't.
diff --git a/llvm/lib/Transforms/Scalar/LoopVersioningLICM.cpp b/llvm/lib/Transforms/Scalar/LoopVersioningLICM.cpp
index 6e91c4f..6b4fc88 100644
--- a/llvm/lib/Transforms/Scalar/LoopVersioningLICM.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopVersioningLICM.cpp
@@ -164,7 +164,6 @@
bool legalLoopInstructions();
bool legalLoopMemoryAccesses();
bool isLoopAlreadyVisited();
- void setNoAliasToLoop(Loop *VerLoop);
bool instructionSafeForVersioning(Instruction *I);
};
@@ -344,6 +343,13 @@
}
LoadAndStoreCounter++;
Value *Ptr = St->getPointerOperand();
+ // Don't allow stores that we don't have runtime checks for, as we won't be
+ // able to mark them noalias meaning they would prevent any code motion.
+ auto &Pointers = LAI->getRuntimePointerChecking()->Pointers;
+ if (!any_of(Pointers, [&](auto &P) { return P.PointerValue == Ptr; })) {
+ LLVM_DEBUG(dbgs() << " Found a store without a runtime check.\n");
+ return false;
+ }
// Check loop invariant.
if (SE->isLoopInvariant(SE->getSCEV(Ptr), CurLoop))
InvariantCounter++;
@@ -361,6 +367,13 @@
InvariantCounter = 0;
IsReadOnlyLoop = true;
using namespace ore;
+ // Get LoopAccessInfo from current loop via the proxy.
+ LAI = &LAIs.getInfo(*CurLoop);
+ // Check LoopAccessInfo for need of runtime check.
+ if (LAI->getRuntimePointerChecking()->getChecks().empty()) {
+ LLVM_DEBUG(dbgs() << " LAA: Runtime check not found !!\n");
+ return false;
+ }
// Iterate over loop blocks and instructions of each block and check
// instruction safety.
for (auto *Block : CurLoop->getBlocks())
@@ -374,13 +387,6 @@
return false;
}
}
- // Get LoopAccessInfo from current loop via the proxy.
- LAI = &LAIs.getInfo(*CurLoop);
- // Check LoopAccessInfo for need of runtime check.
- if (LAI->getRuntimePointerChecking()->getChecks().empty()) {
- LLVM_DEBUG(dbgs() << " LAA: Runtime check not found !!\n");
- return false;
- }
// Number of runtime-checks should be less then RuntimeMemoryCheckThreshold
if (LAI->getNumRuntimePointerChecks() >
VectorizerParams::RuntimeMemoryCheckThreshold) {
@@ -501,41 +507,6 @@
return true;
}
-/// Update loop with aggressive aliasing assumptions.
-/// It marks no-alias to any pairs of memory operations by assuming
-/// loop should not have any must-alias memory accesses pairs.
-/// During LoopVersioningLICM legality we ignore loops having must
-/// aliasing memory accesses.
-void LoopVersioningLICM::setNoAliasToLoop(Loop *VerLoop) {
- // Get latch terminator instruction.
- Instruction *I = VerLoop->getLoopLatch()->getTerminator();
- // Create alias scope domain.
- MDBuilder MDB(I->getContext());
- MDNode *NewDomain = MDB.createAnonymousAliasScopeDomain("LVDomain");
- StringRef Name = "LVAliasScope";
- MDNode *NewScope = MDB.createAnonymousAliasScope(NewDomain, Name);
- SmallVector<Metadata *, 4> Scopes{NewScope}, NoAliases{NewScope};
- // Iterate over each instruction of loop.
- // set no-alias for all load & store instructions.
- for (auto *Block : CurLoop->getBlocks()) {
- for (auto &Inst : *Block) {
- // Only interested in instruction that may modify or read memory.
- if (!Inst.mayReadFromMemory() && !Inst.mayWriteToMemory())
- continue;
- // Set no-alias for current instruction.
- Inst.setMetadata(
- LLVMContext::MD_noalias,
- MDNode::concatenate(Inst.getMetadata(LLVMContext::MD_noalias),
- MDNode::get(Inst.getContext(), NoAliases)));
- // set alias-scope for current instruction.
- Inst.setMetadata(
- LLVMContext::MD_alias_scope,
- MDNode::concatenate(Inst.getMetadata(LLVMContext::MD_alias_scope),
- MDNode::get(Inst.getContext(), Scopes)));
- }
- }
-}
-
bool LoopVersioningLICM::run(DominatorTree *DT) {
// Do not do the transformation if disabled by metadata.
if (hasLICMVersioningTransformation(CurLoop) & TM_Disable)
@@ -563,7 +534,7 @@
addStringMetadataToLoop(LVer.getVersionedLoop(),
"llvm.mem.parallel_loop_access");
// Update version loop with aggressive aliasing assumption.
- setNoAliasToLoop(LVer.getVersionedLoop());
+ LVer.annotateLoopWithNoAlias();
Changed = true;
}
return Changed;
diff --git a/llvm/test/Transforms/LoopVersioningLICM/load-from-unknown-address.ll b/llvm/test/Transforms/LoopVersioningLICM/load-from-unknown-address.ll
new file mode 100644
index 0000000..e9b2954
--- /dev/null
+++ b/llvm/test/Transforms/LoopVersioningLICM/load-from-unknown-address.ll
@@ -0,0 +1,307 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals none --version 5
+; RUN: opt < %s -S -passes='function(loop-versioning-licm,loop-mssa(licm))' | FileCheck %s
+
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128-Fn32"
+
+; In these tests we have a loop where we can calculate the bounds of some memory
+; accesses but not others.
+
+; Load from a gep whose bounds can't be calculated as the offset is loaded from memory
+; FIXME: Not knowing the bounds of the gep shouldn't stop us from hoisting the load of rval
+define void @gep_loaded_offset(ptr %p, ptr %q, ptr %r, i32 %n) {
+; CHECK-LABEL: define void @gep_loaded_offset(
+; CHECK-SAME: ptr [[P:%.*]], ptr [[Q:%.*]], ptr [[R:%.*]], i32 [[N:%.*]]) {
+; CHECK-NEXT: [[ENTRY:.*]]:
+; CHECK-NEXT: br label %[[WHILE_BODY:.*]]
+; CHECK: [[WHILE_BODY]]:
+; CHECK-NEXT: [[N_ADDR:%.*]] = phi i32 [ [[DEC:%.*]], %[[WHILE_BODY]] ], [ [[N]], %[[ENTRY]] ]
+; CHECK-NEXT: [[P_ADDR:%.*]] = phi ptr [ [[INCDEC_PTR:%.*]], %[[WHILE_BODY]] ], [ [[P]], %[[ENTRY]] ]
+; CHECK-NEXT: [[DEC]] = add nsw i32 [[N_ADDR]], -1
+; CHECK-NEXT: [[RVAL:%.*]] = load i64, ptr [[R]], align 4
+; CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds i32, ptr [[Q]], i64 [[RVAL]]
+; CHECK-NEXT: [[VAL:%.*]] = load i32, ptr [[ARRAYIDX]], align 4
+; CHECK-NEXT: [[INCDEC_PTR]] = getelementptr inbounds nuw i8, ptr [[P_ADDR]], i64 4
+; CHECK-NEXT: store i32 [[VAL]], ptr [[P_ADDR]], align 4
+; CHECK-NEXT: [[TOBOOL_NOT:%.*]] = icmp eq i32 [[DEC]], 0
+; CHECK-NEXT: br i1 [[TOBOOL_NOT]], label %[[WHILE_END:.*]], label %[[WHILE_BODY]]
+; CHECK: [[WHILE_END]]:
+; CHECK-NEXT: ret void
+;
+entry:
+ br label %while.body
+
+while.body:
+ %n.addr = phi i32 [ %dec, %while.body ], [ %n, %entry ]
+ %p.addr = phi ptr [ %incdec.ptr, %while.body ], [ %p, %entry ]
+ %dec = add nsw i32 %n.addr, -1
+ %rval = load i64, ptr %r, align 4
+ %arrayidx = getelementptr inbounds i32, ptr %q, i64 %rval
+ %val = load i32, ptr %arrayidx, align 4
+ %incdec.ptr = getelementptr inbounds nuw i8, ptr %p.addr, i64 4
+ store i32 %val, ptr %p.addr, align 4
+ %tobool.not = icmp eq i32 %dec, 0
+ br i1 %tobool.not, label %while.end, label %while.body
+
+while.end:
+ ret void
+}
+
+; As above but with a store to the loaded address. This should prevent the loop
+; from being versioned, as we wouldn't be able to do any code motion.
+define void @gep_loaded_offset_with_store(ptr %p, ptr %q, ptr %r, i32 %n) {
+; CHECK-LABEL: define void @gep_loaded_offset_with_store(
+; CHECK-SAME: ptr [[P:%.*]], ptr [[Q:%.*]], ptr [[R:%.*]], i32 [[N:%.*]]) {
+; CHECK-NEXT: [[ENTRY:.*]]:
+; CHECK-NEXT: br label %[[WHILE_BODY:.*]]
+; CHECK: [[WHILE_BODY]]:
+; CHECK-NEXT: [[N_ADDR:%.*]] = phi i32 [ [[DEC:%.*]], %[[WHILE_BODY]] ], [ [[N]], %[[ENTRY]] ]
+; CHECK-NEXT: [[P_ADDR:%.*]] = phi ptr [ [[INCDEC_PTR:%.*]], %[[WHILE_BODY]] ], [ [[P]], %[[ENTRY]] ]
+; CHECK-NEXT: [[DEC]] = add nsw i32 [[N_ADDR]], -1
+; CHECK-NEXT: [[RVAL:%.*]] = load i64, ptr [[R]], align 4
+; CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds i32, ptr [[Q]], i64 [[RVAL]]
+; CHECK-NEXT: [[VAL:%.*]] = load i32, ptr [[ARRAYIDX]], align 4
+; CHECK-NEXT: store i32 0, ptr [[ARRAYIDX]], align 4
+; CHECK-NEXT: [[INCDEC_PTR]] = getelementptr inbounds nuw i8, ptr [[P_ADDR]], i64 4
+; CHECK-NEXT: store i32 [[VAL]], ptr [[P_ADDR]], align 4
+; CHECK-NEXT: [[TOBOOL_NOT:%.*]] = icmp eq i32 [[DEC]], 0
+; CHECK-NEXT: br i1 [[TOBOOL_NOT]], label %[[WHILE_END:.*]], label %[[WHILE_BODY]]
+; CHECK: [[WHILE_END]]:
+; CHECK-NEXT: ret void
+;
+entry:
+ br label %while.body
+
+while.body:
+ %n.addr = phi i32 [ %dec, %while.body ], [ %n, %entry ]
+ %p.addr = phi ptr [ %incdec.ptr, %while.body ], [ %p, %entry ]
+ %dec = add nsw i32 %n.addr, -1
+ %rval = load i64, ptr %r, align 4
+ %arrayidx = getelementptr inbounds i32, ptr %q, i64 %rval
+ %val = load i32, ptr %arrayidx, align 4
+ store i32 0, ptr %arrayidx, align 4
+ %incdec.ptr = getelementptr inbounds nuw i8, ptr %p.addr, i64 4
+ store i32 %val, ptr %p.addr, align 4
+ %tobool.not = icmp eq i32 %dec, 0
+ br i1 %tobool.not, label %while.end, label %while.body
+
+while.end:
+ ret void
+}
+
+; Load from a gep whose bounds can't be calculated as the pointer is loaded from memory
+; FIXME: Not knowing the bounds of the gep shouldn't stop us from hoisting the load of rval
+define void @gep_loaded_base(ptr %p, ptr %q, ptr %r, i32 %n) {
+; CHECK-LABEL: define void @gep_loaded_base(
+; CHECK-SAME: ptr [[P:%.*]], ptr [[Q:%.*]], ptr [[R:%.*]], i32 [[N:%.*]]) {
+; CHECK-NEXT: [[ENTRY:.*]]:
+; CHECK-NEXT: br label %[[WHILE_BODY:.*]]
+; CHECK: [[WHILE_BODY]]:
+; CHECK-NEXT: [[N_ADDR:%.*]] = phi i32 [ [[DEC:%.*]], %[[WHILE_BODY]] ], [ [[N]], %[[ENTRY]] ]
+; CHECK-NEXT: [[P_ADDR:%.*]] = phi ptr [ [[INCDEC_PTR:%.*]], %[[WHILE_BODY]] ], [ [[P]], %[[ENTRY]] ]
+; CHECK-NEXT: [[DEC]] = add nsw i32 [[N_ADDR]], -1
+; CHECK-NEXT: [[RVAL:%.*]] = load ptr, ptr [[R]], align 4
+; CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds i32, ptr [[RVAL]], i64 0
+; CHECK-NEXT: [[VAL:%.*]] = load i32, ptr [[ARRAYIDX]], align 4
+; CHECK-NEXT: [[INCDEC_PTR]] = getelementptr inbounds nuw i8, ptr [[P_ADDR]], i64 4
+; CHECK-NEXT: store i32 [[VAL]], ptr [[P_ADDR]], align 4
+; CHECK-NEXT: [[TOBOOL_NOT:%.*]] = icmp eq i32 [[DEC]], 0
+; CHECK-NEXT: br i1 [[TOBOOL_NOT]], label %[[WHILE_END:.*]], label %[[WHILE_BODY]]
+; CHECK: [[WHILE_END]]:
+; CHECK-NEXT: ret void
+;
+entry:
+ br label %while.body
+
+while.body:
+ %n.addr = phi i32 [ %dec, %while.body ], [ %n, %entry ]
+ %p.addr = phi ptr [ %incdec.ptr, %while.body ], [ %p, %entry ]
+ %dec = add nsw i32 %n.addr, -1
+ %rval = load ptr, ptr %r, align 4
+ %arrayidx = getelementptr inbounds i32, ptr %rval, i64 0
+ %val = load i32, ptr %arrayidx, align 4
+ %incdec.ptr = getelementptr inbounds nuw i8, ptr %p.addr, i64 4
+ store i32 %val, ptr %p.addr, align 4
+ %tobool.not = icmp eq i32 %dec, 0
+ br i1 %tobool.not, label %while.end, label %while.body
+
+while.end:
+ ret void
+}
+
+; Load from a gep with an offset that scalar evolution can't describe
+; FIXME: Not knowing the bounds of the gep shouldn't stop us from hoisting the load of qval
+define void @gep_strange_offset(ptr %p, ptr %q, ptr %r, i32 %n) {
+; CHECK-LABEL: define void @gep_strange_offset(
+; CHECK-SAME: ptr [[P:%.*]], ptr [[Q:%.*]], ptr [[R:%.*]], i32 [[N:%.*]]) {
+; CHECK-NEXT: [[ENTRY:.*]]:
+; CHECK-NEXT: br label %[[WHILE_BODY:.*]]
+; CHECK: [[WHILE_BODY]]:
+; CHECK-NEXT: [[N_ADDR:%.*]] = phi i32 [ [[DEC:%.*]], %[[WHILE_BODY]] ], [ [[N]], %[[ENTRY]] ]
+; CHECK-NEXT: [[P_ADDR:%.*]] = phi ptr [ [[INCDEC_PTR:%.*]], %[[WHILE_BODY]] ], [ [[P]], %[[ENTRY]] ]
+; CHECK-NEXT: [[DEC]] = add nsw i32 [[N_ADDR]], -1
+; CHECK-NEXT: [[QVAL:%.*]] = load i32, ptr [[Q]], align 4
+; CHECK-NEXT: [[REM:%.*]] = srem i32 [[DEC]], 2
+; CHECK-NEXT: [[IDXPROM:%.*]] = sext i32 [[REM]] to i64
+; CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds i32, ptr [[R]], i64 [[IDXPROM]]
+; CHECK-NEXT: [[VAL:%.*]] = load i32, ptr [[ARRAYIDX]], align 4
+; CHECK-NEXT: [[ADD:%.*]] = add nsw i32 [[VAL]], [[QVAL]]
+; CHECK-NEXT: [[INCDEC_PTR]] = getelementptr inbounds nuw i8, ptr [[P_ADDR]], i64 4
+; CHECK-NEXT: store i32 [[ADD]], ptr [[P_ADDR]], align 4
+; CHECK-NEXT: [[TOBOOL_NOT:%.*]] = icmp eq i32 [[DEC]], 0
+; CHECK-NEXT: br i1 [[TOBOOL_NOT]], label %[[WHILE_END:.*]], label %[[WHILE_BODY]]
+; CHECK: [[WHILE_END]]:
+; CHECK-NEXT: ret void
+;
+entry:
+ br label %while.body
+
+while.body:
+ %n.addr = phi i32 [ %dec, %while.body ], [ %n, %entry ]
+ %p.addr = phi ptr [ %incdec.ptr, %while.body ], [ %p, %entry ]
+ %dec = add nsw i32 %n.addr, -1
+ %qval = load i32, ptr %q, align 4
+ %rem = srem i32 %dec, 2
+ %idxprom = sext i32 %rem to i64
+ %arrayidx = getelementptr inbounds i32, ptr %r, i64 %idxprom
+ %val = load i32, ptr %arrayidx, align 4
+ %add = add nsw i32 %val, %qval
+ %incdec.ptr = getelementptr inbounds nuw i8, ptr %p.addr, i64 4
+ store i32 %add, ptr %p.addr, align 4
+ %tobool.not = icmp eq i32 %dec, 0
+ br i1 %tobool.not, label %while.end, label %while.body
+
+while.end:
+ ret void
+}
+
+; A memcpy-like loop where the source address is loaded from a pointer
+; FIXME: We should be able to hoist the load of the source address pointer
+define void @memcpy_load_src(ptr %dst, ptr %src, i32 %n) {
+; CHECK-LABEL: define void @memcpy_load_src(
+; CHECK-SAME: ptr [[DST:%.*]], ptr [[SRC:%.*]], i32 [[N:%.*]]) {
+; CHECK-NEXT: [[ENTRY:.*]]:
+; CHECK-NEXT: br label %[[WHILE_BODY:.*]]
+; CHECK: [[WHILE_BODY]]:
+; CHECK-NEXT: [[N_VAL:%.*]] = phi i32 [ [[DEC:%.*]], %[[WHILE_BODY]] ], [ [[N]], %[[ENTRY]] ]
+; CHECK-NEXT: [[DST_VAL:%.*]] = phi ptr [ [[DST_VAL_NEXT:%.*]], %[[WHILE_BODY]] ], [ [[DST]], %[[ENTRY]] ]
+; CHECK-NEXT: [[DEC]] = add nsw i32 [[N_VAL]], -1
+; CHECK-NEXT: [[SRC_VAL:%.*]] = load ptr, ptr [[SRC]], align 8
+; CHECK-NEXT: [[SRC_VAL_NEXT:%.*]] = getelementptr inbounds nuw i8, ptr [[SRC_VAL]], i64 1
+; CHECK-NEXT: [[DST_VAL_NEXT]] = getelementptr inbounds nuw i8, ptr [[DST_VAL]], i64 1
+; CHECK-NEXT: store ptr [[SRC_VAL_NEXT]], ptr [[SRC]], align 8
+; CHECK-NEXT: [[VAL:%.*]] = load i8, ptr [[SRC_VAL]], align 1
+; CHECK-NEXT: store i8 [[VAL]], ptr [[DST_VAL]], align 1
+; CHECK-NEXT: [[TOBOOL_NOT:%.*]] = icmp eq i32 [[DEC]], 0
+; CHECK-NEXT: br i1 [[TOBOOL_NOT]], label %[[WHILE_END:.*]], label %[[WHILE_BODY]]
+; CHECK: [[WHILE_END]]:
+; CHECK-NEXT: ret void
+;
+entry:
+ br label %while.body
+
+while.body:
+ %n_val = phi i32 [ %dec, %while.body ], [ %n, %entry ]
+ %dst_val = phi ptr [ %dst_val.next, %while.body ], [ %dst, %entry ]
+ %dec = add nsw i32 %n_val, -1
+ %src_val = load ptr, ptr %src, align 8
+ %src_val.next = getelementptr inbounds nuw i8, ptr %src_val, i64 1
+ %dst_val.next = getelementptr inbounds nuw i8, ptr %dst_val, i64 1
+ store ptr %src_val.next, ptr %src, align 8
+ %val = load i8, ptr %src_val, align 1
+ store i8 %val, ptr %dst_val, align 1
+ %tobool.not = icmp eq i32 %dec, 0
+ br i1 %tobool.not, label %while.end, label %while.body
+
+while.end:
+ ret void
+}
+
+; A memcpy-like loop where the destination address is loaded from a pointer
+; FIXME: We could hoist the load of the destination address, but doing the
+; bounds check of the store through that pointer itself requires using the
+; hoisted load.
+define void @memcpy_load_dst(ptr %dst, ptr %src, i32 %n) {
+; CHECK-LABEL: define void @memcpy_load_dst(
+; CHECK-SAME: ptr [[DST:%.*]], ptr [[SRC:%.*]], i32 [[N:%.*]]) {
+; CHECK-NEXT: [[ENTRY:.*]]:
+; CHECK-NEXT: br label %[[WHILE_BODY:.*]]
+; CHECK: [[WHILE_BODY]]:
+; CHECK-NEXT: [[N_VAL:%.*]] = phi i32 [ [[DEC:%.*]], %[[WHILE_BODY]] ], [ [[N]], %[[ENTRY]] ]
+; CHECK-NEXT: [[SRC_VAL:%.*]] = phi ptr [ [[SRC_VAL_NEXT:%.*]], %[[WHILE_BODY]] ], [ [[SRC]], %[[ENTRY]] ]
+; CHECK-NEXT: [[DEC]] = add nsw i32 [[N_VAL]], -1
+; CHECK-NEXT: [[DST_VAL:%.*]] = load ptr, ptr [[DST]], align 8
+; CHECK-NEXT: [[SRC_VAL_NEXT]] = getelementptr inbounds nuw i8, ptr [[SRC_VAL]], i64 1
+; CHECK-NEXT: [[DST_VAL_NEXT:%.*]] = getelementptr inbounds nuw i8, ptr [[DST_VAL]], i64 1
+; CHECK-NEXT: store ptr [[DST_VAL_NEXT]], ptr [[DST]], align 8
+; CHECK-NEXT: [[VAL:%.*]] = load i8, ptr [[SRC_VAL]], align 1
+; CHECK-NEXT: store i8 [[VAL]], ptr [[DST_VAL]], align 1
+; CHECK-NEXT: [[TOBOOL_NOT:%.*]] = icmp eq i32 [[DEC]], 0
+; CHECK-NEXT: br i1 [[TOBOOL_NOT]], label %[[WHILE_END:.*]], label %[[WHILE_BODY]]
+; CHECK: [[WHILE_END]]:
+; CHECK-NEXT: ret void
+;
+entry:
+ br label %while.body
+
+while.body:
+ %n_val = phi i32 [ %dec, %while.body ], [ %n, %entry ]
+ %src_val = phi ptr [ %src_val.next, %while.body ], [ %src, %entry ]
+ %dec = add nsw i32 %n_val, -1
+ %dst_val = load ptr, ptr %dst, align 8
+ %src_val.next = getelementptr inbounds nuw i8, ptr %src_val, i64 1
+ %dst_val.next = getelementptr inbounds nuw i8, ptr %dst_val, i64 1
+ store ptr %dst_val.next, ptr %dst, align 8
+ %val = load i8, ptr %src_val, align 1
+ store i8 %val, ptr %dst_val, align 1
+ %tobool.not = icmp eq i32 %dec, 0
+ br i1 %tobool.not, label %while.end, label %while.body
+
+while.end:
+ ret void
+}
+
+; A memcpy-like loop where both the source and destination pointers are loaded from pointers
+; FIXME: We could hoist the loads of both addresses, but doing the bounds check
+; of the store through the destination address itself requires using the hoisted
+; load.
+define void @memcpy_load_src_dst(ptr %dst, ptr %src, i32 %n) {
+; CHECK-LABEL: define void @memcpy_load_src_dst(
+; CHECK-SAME: ptr [[DST:%.*]], ptr [[SRC:%.*]], i32 [[N:%.*]]) {
+; CHECK-NEXT: [[ENTRY:.*]]:
+; CHECK-NEXT: br label %[[WHILE_BODY:.*]]
+; CHECK: [[WHILE_BODY]]:
+; CHECK-NEXT: [[N_VAL:%.*]] = phi i32 [ [[DEC:%.*]], %[[WHILE_BODY]] ], [ [[N]], %[[ENTRY]] ]
+; CHECK-NEXT: [[DEC]] = add nsw i32 [[N_VAL]], -1
+; CHECK-NEXT: [[SRC_VAL:%.*]] = load ptr, ptr [[SRC]], align 8
+; CHECK-NEXT: [[DST_VAL:%.*]] = load ptr, ptr [[DST]], align 8
+; CHECK-NEXT: [[SRC_VAL_NEXT:%.*]] = getelementptr inbounds nuw i8, ptr [[SRC_VAL]], i64 1
+; CHECK-NEXT: [[DST_VAL_NEXT:%.*]] = getelementptr inbounds nuw i8, ptr [[DST_VAL]], i64 1
+; CHECK-NEXT: store ptr [[SRC_VAL_NEXT]], ptr [[SRC]], align 8
+; CHECK-NEXT: store ptr [[DST_VAL_NEXT]], ptr [[DST]], align 8
+; CHECK-NEXT: [[VAL:%.*]] = load i8, ptr [[SRC_VAL]], align 1
+; CHECK-NEXT: store i8 [[VAL]], ptr [[DST_VAL]], align 1
+; CHECK-NEXT: [[TOBOOL_NOT:%.*]] = icmp eq i32 [[DEC]], 0
+; CHECK-NEXT: br i1 [[TOBOOL_NOT]], label %[[WHILE_END:.*]], label %[[WHILE_BODY]]
+; CHECK: [[WHILE_END]]:
+; CHECK-NEXT: ret void
+;
+entry:
+ br label %while.body
+
+while.body:
+ %n_val = phi i32 [ %dec, %while.body ], [ %n, %entry ]
+ %dec = add nsw i32 %n_val, -1
+ %src_val = load ptr, ptr %src, align 8
+ %dst_val = load ptr, ptr %dst, align 8
+ %src_val.next = getelementptr inbounds nuw i8, ptr %src_val, i64 1
+ %dst_val.next = getelementptr inbounds nuw i8, ptr %dst_val, i64 1
+ store ptr %src_val.next, ptr %src, align 8
+ store ptr %dst_val.next, ptr %dst, align 8
+ %val = load i8, ptr %src_val, align 1
+ store i8 %val, ptr %dst_val, align 1
+ %tobool.not = icmp eq i32 %dec, 0
+ br i1 %tobool.not, label %while.end, label %while.body
+
+while.end:
+ ret void
+}
diff --git a/llvm/test/Transforms/LoopVersioningLICM/loopversioningLICM1.ll b/llvm/test/Transforms/LoopVersioningLICM/loopversioningLICM1.ll
index 3f9bd93..b4f8abb 100644
--- a/llvm/test/Transforms/LoopVersioningLICM/loopversioningLICM1.ll
+++ b/llvm/test/Transforms/LoopVersioningLICM/loopversioningLICM1.ll
@@ -57,23 +57,23 @@
; CHECK-NEXT: [[CMP2_LVER_ORIG:%.*]] = icmp ult i32 [[INC_LVER_ORIG]], [[ITR]]
; CHECK-NEXT: br i1 [[CMP2_LVER_ORIG]], label [[FOR_BODY3_LVER_ORIG]], label [[FOR_INC11_LOOPEXIT_LOOPEXIT:%.*]], !llvm.loop [[LOOP0:![0-9]+]]
; CHECK: for.body3.ph:
-; CHECK-NEXT: [[ARRAYIDX7_PROMOTED:%.*]] = load i32, ptr [[ARRAYIDX7]], align 4, !alias.scope [[META2:![0-9]+]], !noalias [[META2]]
+; CHECK-NEXT: [[ARRAYIDX7_PROMOTED:%.*]] = load i32, ptr [[ARRAYIDX7]], align 4, !alias.scope [[META2:![0-9]+]]
; CHECK-NEXT: br label [[FOR_BODY3:%.*]]
; CHECK: for.body3:
; CHECK-NEXT: [[ADD86:%.*]] = phi i32 [ [[ARRAYIDX7_PROMOTED]], [[FOR_BODY3_PH]] ], [ [[ADD8:%.*]], [[FOR_BODY3]] ]
; CHECK-NEXT: [[J_113:%.*]] = phi i32 [ [[J_016]], [[FOR_BODY3_PH]] ], [ [[INC:%.*]], [[FOR_BODY3]] ]
; CHECK-NEXT: [[IDXPROM:%.*]] = zext i32 [[J_113]] to i64
; CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds nuw i32, ptr [[VAR1]], i64 [[IDXPROM]]
-; CHECK-NEXT: store i32 [[ADD]], ptr [[ARRAYIDX]], align 4, !alias.scope [[META2]], !noalias [[META2]]
+; CHECK-NEXT: store i32 [[ADD]], ptr [[ARRAYIDX]], align 4, !alias.scope [[META5:![0-9]+]], !noalias [[META2]]
; CHECK-NEXT: [[ADD8]] = add nsw i32 [[ADD86]], [[ADD]]
; CHECK-NEXT: [[INC]] = add nuw i32 [[J_113]], 1
; CHECK-NEXT: [[CMP2:%.*]] = icmp ult i32 [[INC]], [[ITR]]
-; CHECK-NEXT: br i1 [[CMP2]], label [[FOR_BODY3]], label [[FOR_INC11_LOOPEXIT_LOOPEXIT5:%.*]], !llvm.loop [[LOOP5:![0-9]+]]
+; CHECK-NEXT: br i1 [[CMP2]], label [[FOR_BODY3]], label [[FOR_INC11_LOOPEXIT_LOOPEXIT5:%.*]], !llvm.loop [[LOOP7:![0-9]+]]
; CHECK: for.inc11.loopexit.loopexit:
; CHECK-NEXT: br label [[FOR_INC11_LOOPEXIT:%.*]]
; CHECK: for.inc11.loopexit.loopexit5:
; CHECK-NEXT: [[ADD8_LCSSA:%.*]] = phi i32 [ [[ADD8]], [[FOR_BODY3]] ]
-; CHECK-NEXT: store i32 [[ADD8_LCSSA]], ptr [[ARRAYIDX7]], align 4, !alias.scope [[META2]], !noalias [[META2]]
+; CHECK-NEXT: store i32 [[ADD8_LCSSA]], ptr [[ARRAYIDX7]], align 4, !alias.scope [[META2]]
; CHECK-NEXT: br label [[FOR_INC11_LOOPEXIT]]
; CHECK: for.inc11.loopexit:
; CHECK-NEXT: br label [[FOR_INC11]]
diff --git a/llvm/test/Transforms/LoopVersioningLICM/loopversioningLICM2.ll b/llvm/test/Transforms/LoopVersioningLICM/loopversioningLICM2.ll
index 22ca534..a31da2a 100644
--- a/llvm/test/Transforms/LoopVersioningLICM/loopversioningLICM2.ll
+++ b/llvm/test/Transforms/LoopVersioningLICM/loopversioningLICM2.ll
@@ -9,7 +9,7 @@
;
; CHECK: for.cond1.for.inc17_crit_edge.us.loopexit5: ; preds = %for.body3.us
; CHECK-NEXT: %add14.us.lcssa = phi float [ %add14.us, %for.body3.us ]
-; CHECK-NEXT: store float %add14.us.lcssa, ptr %arrayidx.us, align 4, !alias.scope !0, !noalias !0
+; CHECK-NEXT: store float %add14.us.lcssa, ptr %arrayidx.us, align 4, !alias.scope !3
; CHECK-NEXT: br label %for.cond1.for.inc17_crit_edge.us
;
define i32 @foo(ptr nocapture %var2, ptr nocapture readonly %var3, i32 %itr) #0 {
