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1; RUN: llc < %s -mtriple=bpf -mattr=+alu32 -verify-machineinstrs | FileCheck %s2;3; Source:4; struct __sk_buff {5; unsigned data;6; unsigned data_end;7; };8;9; ptr test(int flag, struct __sk_buff *skb)10; {11; ptr p;12;13; if (flag) {14; p = (ptr)(long)skb->data;15; __asm__ __volatile__("": : :"memory");16; } else {17; p = (ptr)(long)skb->data_end;18; __asm__ __volatile__("": : :"memory");19; }20;21; return p;22; }23; Compilation flag:24; clang -target bpf -O2 -S -emit-llvm t.c25 26%struct.__sk_buff = type { i32, i32 }27 28define dso_local ptr @test(i32 %flag, ptr nocapture readonly %skb) local_unnamed_addr {29entry:30 %tobool = icmp eq i32 %flag, 031 br i1 %tobool, label %if.else, label %if.then32 33if.then:34 %0 = load i32, ptr %skb, align 435 tail call void asm sideeffect "", "~{memory}"()36 br label %if.end37 38if.else:39 %data_end = getelementptr inbounds %struct.__sk_buff, ptr %skb, i64 0, i32 140 %1 = load i32, ptr %data_end, align 441 tail call void asm sideeffect "", "~{memory}"()42 br label %if.end43 44if.end:45 %p.0.in.in = phi i32 [ %0, %if.then ], [ %1, %if.else ]46 %p.0.in = zext i32 %p.0.in.in to i6447 %p.0 = inttoptr i64 %p.0.in to ptr48 ret ptr %p.049}50 51; CHECK: w0 = *(u32 *)(r2 + 0)52; CHECK: w0 = *(u32 *)(r2 + 4)53; CHECK-NOT: r[[#]] = w[[#]]54; CHECK: exit55