109 lines · plain
1; RUN: opt -O2 -mtriple=bpf-pc-linux -S -o - %s | FileCheck %s2;3; Check position of bpf-preserve-static-offset pass in the pipeline:4; - preserve.static.offset call is preserved if address is passed as5; a parameter to an inline-able function;6; - second bpf-preserve-static-offset pass (after inlining) should introduce7; getelementptr.and.load call using the preserved marker after loops8; unrolling;9; - readonly and tbaa attributes should allow replacement of10; getelementptr.and.load calls by CSE transformation.11;12; Source:13; #define __ctx __attribute__((preserve_static_offset))14; 15; struct foo {16; int a;17; int b[4];18; } __ctx;19; 20; extern void consume(int);21; 22; static inline void bar(int * restrict p) {23; consume(p[1]);24; }25; 26; void quux(struct foo *p){27; unsigned long i = 0;28; #pragma clang loop unroll(full)29; while (i < 2) {30; bar(p->b);31; ++i;32; }33; }34;35; Compilation flag:36; clang -cc1 -O2 -triple bpf -S -emit-llvm -disable-llvm-passes -o - \37; | opt -passes=function(sroa) -S -o -38 39%struct.foo = type { i32, [4 x i32] }40 41; Function Attrs: nounwind42define dso_local void @quux(ptr noundef %p) #0 {43entry:44 br label %while.cond45 46while.cond: ; preds = %while.body, %entry47 %i.0 = phi i64 [ 0, %entry ], [ %inc, %while.body ]48 %cmp = icmp ult i64 %i.0, 249 br i1 %cmp, label %while.body, label %while.end50 51while.body: ; preds = %while.cond52 %0 = call ptr @llvm.preserve.static.offset(ptr %p)53 %b = getelementptr inbounds %struct.foo, ptr %0, i32 0, i32 154 %arraydecay = getelementptr inbounds [4 x i32], ptr %b, i64 0, i64 055 call void @bar(ptr noundef %arraydecay)56 %inc = add i64 %i.0, 157 br label %while.cond, !llvm.loop !258 59while.end: ; preds = %while.cond60 ret void61}62 63; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)64declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #165 66; Function Attrs: inlinehint nounwind67define internal void @bar(ptr noalias noundef %p) #2 {68entry:69 %arrayidx = getelementptr inbounds i32, ptr %p, i64 170 %0 = load i32, ptr %arrayidx, align 4, !tbaa !571 call void @consume(i32 noundef %0)72 ret void73}74 75; CHECK: define dso_local void @quux(ptr noundef readonly captures(none) %[[p:.*]])76; CHECK: %[[v1:.*]] = tail call i32 (ptr, i1, i8, i8, i8, i1, ...)77; CHECK-SAME: @llvm.bpf.getelementptr.and.load.i3278; CHECK-SAME: (ptr readonly elementtype(i8) %[[p]],79; CHECK-SAME: i1 false, i8 0, i8 1, i8 2, i1 true, i64 immarg 8)80; CHECK: tail call void @consume(i32 noundef %[[v1]])81; CHECK: tail call void @consume(i32 noundef %[[v1]])82 83; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)84declare ptr @llvm.preserve.static.offset(ptr readnone) #385 86; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)87declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #188 89declare void @consume(i32 noundef) #490 91attributes #0 = { nounwind "no-trapping-math"="true" "stack-protector-buffer-size"="8" }92attributes #1 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }93attributes #2 = { inlinehint nounwind "no-trapping-math"="true" "stack-protector-buffer-size"="8" }94attributes #3 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }95attributes #4 = { "no-trapping-math"="true" "stack-protector-buffer-size"="8" }96 97!llvm.module.flags = !{!0}98!llvm.ident = !{!1}99 100!0 = !{i32 1, !"wchar_size", i32 4}101!1 = !{!"clang"}102!2 = distinct !{!2, !3, !4}103!3 = !{!"llvm.loop.mustprogress"}104!4 = !{!"llvm.loop.unroll.full"}105!5 = !{!6, !6, i64 0}106!6 = !{!"int", !7, i64 0}107!7 = !{!"omnipotent char", !8, i64 0}108!8 = !{!"Simple C/C++ TBAA"}109