llvm-project/llvm/test/CodeGen/AVR/avr-rust-issue-123.ll

75 lines
2.4 KiB
LLVM

; RUN: llc -O1 < %s -march=avr | FileCheck %s
; This test ensures that the Select8/Select16 expansion
; pass inserts an unconditional branch to the previous adjacent
; basic block when inserting new basic blocks when the
; prior block has a fallthrough.
;
; Before this bug was fixed, Select8/Select16 expansion
; would leave a dangling fallthrough to an undefined block.
;
; The BranchFolding pass would later rearrange the basic
; blocks based on predecessor/successor list assumptions
; which were made incorrect due to the invalid Select
; expansion.
; More information in
; https://github.com/avr-rust/rust/issues/123.
%UInt8 = type <{ i8 }>
%UInt32 = type <{ i32 }>
%Sb = type <{ i1 }>
@delayFactor = hidden global %UInt8 zeroinitializer, align 1
@delay = hidden global %UInt32 zeroinitializer, align 4
@flag = hidden global %Sb zeroinitializer, align 1
declare void @eeprom_write(i16, i8)
; CHECK-LABEL: update_register
define hidden void @update_register(i8 %arg, i8 %arg1) {
entry:
; CHECK: push [[PRELUDER:r[0-9]+]]
; CHECK: cpi r24, 7
switch i8 %arg, label %bb7 [
i8 6, label %bb
i8 7, label %bb6
]
; CHECK-NOT: ret
bb: ; preds = %entry
%tmp = icmp ugt i8 %arg1, 90
%tmp2 = icmp ult i8 %arg1, 5
%. = select i1 %tmp2, i8 5, i8 %arg1
%tmp3 = select i1 %tmp, i8 90, i8 %.
; CHECK: sts delayFactor, r{{[0-9]+}}
store i8 %tmp3, i8* getelementptr inbounds (%UInt8, %UInt8* @delayFactor, i64 0, i32 0), align 1
%tmp4 = zext i8 %tmp3 to i32
%tmp5 = mul nuw nsw i32 %tmp4, 100
; CHECK: sts delay+3, r{{[0-9]+}}
; CHECK-NEXT: sts delay+2, r{{[0-9]+}}
; CHECK-NEXT: sts delay+1, r{{[0-9]+}}
; CHECK-NEXT: sts delay, r{{[0-9]+}}
store i32 %tmp5, i32* getelementptr inbounds (%UInt32, %UInt32* @delay, i64 0, i32 0), align 4
tail call void @eeprom_write(i16 34, i8 %tmp3)
br label %bb7
bb6: ; preds = %entry
%not. = icmp ne i8 %arg1, 0
%.2 = zext i1 %not. to i8
store i1 %not., i1* getelementptr inbounds (%Sb, %Sb* @flag, i64 0, i32 0), align 1
; CHECK: call eeprom_write
tail call void @eeprom_write(i16 35, i8 %.2)
br label %bb7
; CHECK: LBB0_{{[0-9]+}}
; CHECK: pop [[PRELUDER]]
; CHECK-NEXT: ret
bb7: ; preds = %bb6, %bb, %entry
ret void
}
; CHECK-NOT: LBB0_{{[0-9]+}}:
; CHECK-LABEL: .Lfunc_end0
; CHECK: .size update_register, .Lfunc_end0-update_register