87 changes: 87 additions & 0 deletions llvm/test/CodeGen/BPF/remove_truncate_1.ll
Original file line number Diff line number Diff line change
@@ -0,0 +1,87 @@
; RUN: llc < %s -march=bpf -verify-machineinstrs | FileCheck %s

; Source code:
; struct xdp_md {
; unsigned data;
; unsigned data_end;
; };
;
; int gbl;
; int xdp_dummy(struct xdp_md *xdp)
; {
; char tmp;
; long addr;
;
; if (gbl) {
; long addr1 = (long)xdp->data;
; tmp = *(char *)addr1;
; if (tmp == 1)
; return 3;
; } else {
; tmp = *(volatile char *)(long)xdp->data_end;
; if (tmp == 1)
; return 2;
; }
; addr = (long)xdp->data;
; tmp = *(volatile char *)addr;
; if (tmp == 0)
; return 1;
; return 0;
; }

%struct.xdp_md = type { i32, i32 }

@gbl = common local_unnamed_addr global i32 0, align 4

; Function Attrs: norecurse nounwind
define i32 @xdp_dummy(%struct.xdp_md* nocapture readonly %xdp) local_unnamed_addr #0 {
entry:
%0 = load i32, i32* @gbl, align 4
%tobool = icmp eq i32 %0, 0
br i1 %tobool, label %if.else, label %if.then

if.then: ; preds = %entry
%data = getelementptr inbounds %struct.xdp_md, %struct.xdp_md* %xdp, i64 0, i32 0
%1 = load i32, i32* %data, align 4
%conv = zext i32 %1 to i64
%2 = inttoptr i64 %conv to i8*
%3 = load i8, i8* %2, align 1
%cmp = icmp eq i8 %3, 1
br i1 %cmp, label %cleanup20, label %if.end12
; CHECK: r1 = *(u32 *)(r1 + 0)
; CHECK: r2 = *(u8 *)(r1 + 0)

if.else: ; preds = %entry
%data_end = getelementptr inbounds %struct.xdp_md, %struct.xdp_md* %xdp, i64 0, i32 1
%4 = load i32, i32* %data_end, align 4
%conv6 = zext i32 %4 to i64
; CHECK: r2 = *(u32 *)(r1 + 4)
%5 = inttoptr i64 %conv6 to i8*
%6 = load volatile i8, i8* %5, align 1
%cmp8 = icmp eq i8 %6, 1
br i1 %cmp8, label %cleanup20, label %if.else.if.end12_crit_edge

if.else.if.end12_crit_edge: ; preds = %if.else
%data13.phi.trans.insert = getelementptr inbounds %struct.xdp_md, %struct.xdp_md* %xdp, i64 0, i32 0
%.pre = load i32, i32* %data13.phi.trans.insert, align 4
br label %if.end12
; CHECK: r1 = *(u32 *)(r1 + 0)

if.end12: ; preds = %if.else.if.end12_crit_edge, %if.then
%7 = phi i32 [ %.pre, %if.else.if.end12_crit_edge ], [ %1, %if.then ]
%conv14 = zext i32 %7 to i64
; CHECK-NOT: r1 <<= 32
; CHECK-NOT: r1 >>= 32
%8 = inttoptr i64 %conv14 to i8*
%9 = load volatile i8, i8* %8, align 1
; CHECK: r1 = *(u8 *)(r1 + 0)
%cmp16 = icmp eq i8 %9, 0
%.28 = zext i1 %cmp16 to i32
br label %cleanup20

cleanup20: ; preds = %if.then, %if.end12, %if.else
%retval.1 = phi i32 [ 3, %if.then ], [ 2, %if.else ], [ %.28, %if.end12 ]
ret i32 %retval.1
}

attributes #0 = { norecurse nounwind }
65 changes: 65 additions & 0 deletions llvm/test/CodeGen/BPF/remove_truncate_2.ll
Original file line number Diff line number Diff line change
@@ -0,0 +1,65 @@
; RUN: llc < %s -march=bpf -verify-machineinstrs | FileCheck %s

; Source code:
; struct xdp_md {
; unsigned data;
; unsigned data_end;
; };
;
; int gbl;
; int xdp_dummy(struct xdp_md *xdp)
; {
; char addr = *(char *)(long)xdp->data;
; if (gbl) {
; if (gbl == 1)
; return 1;
; if (addr == 1)
; return 3;
; } else if (addr == 0)
; return 2;
; return 0;
; }

%struct.xdp_md = type { i32, i32 }

@gbl = common local_unnamed_addr global i32 0, align 4

; Function Attrs: norecurse nounwind readonly
define i32 @xdp_dummy(%struct.xdp_md* nocapture readonly %xdp) local_unnamed_addr #0 {
entry:
%data = getelementptr inbounds %struct.xdp_md, %struct.xdp_md* %xdp, i64 0, i32 0
%0 = load i32, i32* %data, align 4
%conv = zext i32 %0 to i64
%1 = inttoptr i64 %conv to i8*
%2 = load i8, i8* %1, align 1
; CHECK: r1 = *(u32 *)(r1 + 0)
; CHECK: r1 = *(u8 *)(r1 + 0)
%3 = load i32, i32* @gbl, align 4
switch i32 %3, label %if.end [
i32 0, label %if.else
i32 1, label %cleanup
]

if.end: ; preds = %entry
%cmp4 = icmp eq i8 %2, 1
; CHECK: r0 = 3
; CHECK-NOT: r1 &= 255
; CHECK: if r1 == 1 goto
br i1 %cmp4, label %cleanup, label %if.end13

if.else: ; preds = %entry
%cmp9 = icmp eq i8 %2, 0
; CHECK: r0 = 2
; CHECK-NOT: r1 &= 255
; CHECK: if r1 == 0 goto
br i1 %cmp9, label %cleanup, label %if.end13

if.end13: ; preds = %if.else, %if.end
br label %cleanup

cleanup: ; preds = %if.else, %if.end, %entry, %if.end13
%retval.0 = phi i32 [ 0, %if.end13 ], [ 1, %entry ], [ 3, %if.end ], [ 2, %if.else ]
ret i32 %retval.0
}

attributes #0 = { norecurse nounwind readonly }