Index: lib/Target/AArch64/AArch64LoadStoreOptimizer.cpp =================================================================== --- lib/Target/AArch64/AArch64LoadStoreOptimizer.cpp +++ lib/Target/AArch64/AArch64LoadStoreOptimizer.cpp @@ -1253,8 +1253,11 @@ if (MIIsUnscaled) { // If the unscaled offset isn't a multiple of the MemSize, we can't // pair the operations together: bail and keep looking. - if (MIOffset % MemSize) + if (MIOffset % MemSize) { + trackRegDefsUses(MI, ModifiedRegs, UsedRegs, TRI); + MemInsns.push_back(&MI); continue; + } MIOffset /= MemSize; } else { MIOffset *= MemSize; Index: test/CodeGen/AArch64/ldst-paired-aliasing.ll =================================================================== --- /dev/null +++ test/CodeGen/AArch64/ldst-paired-aliasing.ll @@ -0,0 +1,47 @@ +; RUN: llc -mcpu cortex-a53 < %s | FileCheck %s +target datalayout = "e-m:e-i64:64-i128:128-n8:16:32:64-S128" +target triple = "aarch64--linux-gnu" + +declare void @f(i8*, i8*) +declare void @f2(i8*, i8*) +declare void @_Z5setupv() +declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i32, i1) #3 + +define i32 @main() local_unnamed_addr #1 { +; Make sure the stores happen in the correct order (the exact instructions could change). +; CHECK-LABEL: main: +; CHECK: str q0, [sp, #48] +; CHECK: ldr w8, [sp, #48] +; CHECK: stur q1, [sp, #72] +; CHECK: str q0, [sp, #64] +; CHECK: str w9, [sp, #80] + +for.body.lr.ph.i.i.i.i.i.i63: + %b1 = alloca [10 x i32], align 16 + %x0 = bitcast [10 x i32]* %b1 to i8* + %b2 = alloca [10 x i32], align 16 + %x1 = bitcast [10 x i32]* %b2 to i8* + tail call void @_Z5setupv() + %x2 = getelementptr inbounds [10 x i32], [10 x i32]* %b1, i64 0, i64 6 + %x3 = bitcast i32* %x2 to i8* + call void @llvm.memset.p0i8.i64(i8* %x3, i8 0, i64 16, i32 8, i1 false) + %arraydecay2 = getelementptr inbounds [10 x i32], [10 x i32]* %b1, i64 0, i64 0 + %x4 = bitcast [10 x i32]* %b1 to <4 x i32>* + store <4 x i32> , <4 x i32>* %x4, align 16 + %incdec.ptr.i7.i.i.i.i.i.i64.3 = getelementptr inbounds [10 x i32], [10 x i32]* %b1, i64 0, i64 4 + %x5 = bitcast i32* %incdec.ptr.i7.i.i.i.i.i.i64.3 to <4 x i32>* + store <4 x i32> , <4 x i32>* %x5, align 16 + %incdec.ptr.i7.i.i.i.i.i.i64.7 = getelementptr inbounds [10 x i32], [10 x i32]* %b1, i64 0, i64 8 + store i32 1, i32* %incdec.ptr.i7.i.i.i.i.i.i64.7, align 16 + %x6 = load i32, i32* %arraydecay2, align 16 + %cmp6 = icmp eq i32 %x6, 1 + br i1 %cmp6, label %for.inc, label %if.then + +for.inc: + call void @f(i8* %x0, i8* %x1) + ret i32 0 + +if.then: + call void @f2(i8* %x0, i8* %x1) + ret i32 0 +}