llvm-project/llvm/test/CodeGen/Thumb/stack-access.ll

90 lines
2.3 KiB
LLVM

; RUN: llc -mtriple=thumb-eabi < %s -o - | FileCheck %s
; Check that stack addresses are generated using a single ADD
define void @test1(i8** %p) {
%x = alloca i8, align 1
%y = alloca i8, align 1
%z = alloca i8, align 1
; CHECK: add r1, sp, #8
; CHECK: str r1, [r0]
store i8* %x, i8** %p, align 4
; CHECK: add r1, sp, #4
; CHECK: str r1, [r0]
store i8* %y, i8** %p, align 4
; CHECK: mov r1, sp
; CHECK: str r1, [r0]
store i8* %z, i8** %p, align 4
ret void
}
; Stack offsets larger than 1020 still need two ADDs
define void @test2([1024 x i8]** %p) {
%arr1 = alloca [1024 x i8], align 1
%arr2 = alloca [1024 x i8], align 1
; CHECK: add r1, sp, #1020
; CHECK: adds r1, #4
; CHECK: str r1, [r0]
store [1024 x i8]* %arr1, [1024 x i8]** %p, align 4
; CHECK: mov r1, sp
; CHECK: str r1, [r0]
store [1024 x i8]* %arr2, [1024 x i8]** %p, align 4
ret void
}
; If possible stack-based lrdb/ldrh are widened to use SP-based addressing
define i32 @test3() #0 {
%x = alloca i8, align 1
%y = alloca i8, align 1
; CHECK: ldr r0, [sp]
%1 = load i8, i8* %x, align 1
; CHECK: ldr r1, [sp, #4]
%2 = load i8, i8* %y, align 1
%3 = add nsw i8 %1, %2
%4 = zext i8 %3 to i32
ret i32 %4
}
define i32 @test4() #0 {
%x = alloca i16, align 2
%y = alloca i16, align 2
; CHECK: ldr r0, [sp]
%1 = load i16, i16* %x, align 2
; CHECK: ldr r1, [sp, #4]
%2 = load i16, i16* %y, align 2
%3 = add nsw i16 %1, %2
%4 = zext i16 %3 to i32
ret i32 %4
}
; Don't widen if the value needs to be zero-extended
define zeroext i8 @test5() {
%x = alloca i8, align 1
; CHECK: mov r0, sp
; CHECK: ldrb r0, [r0]
%1 = load i8, i8* %x, align 1
ret i8 %1
}
define zeroext i16 @test6() {
%x = alloca i16, align 2
; CHECK: mov r0, sp
; CHECK: ldrh r0, [r0]
%1 = load i16, i16* %x, align 2
ret i16 %1
}
; Accessing the bottom of a large array shouldn't require materializing a base
define void @test7() {
%arr = alloca [200 x i32], align 4
; CHECK: movs [[REG:r[0-9]+]], #1
; CHECK: str [[REG]], [sp, #4]
%arrayidx = getelementptr inbounds [200 x i32], [200 x i32]* %arr, i32 0, i32 1
store i32 1, i32* %arrayidx, align 4
; CHECK: str [[REG]], [sp, #16]
%arrayidx1 = getelementptr inbounds [200 x i32], [200 x i32]* %arr, i32 0, i32 4
store i32 1, i32* %arrayidx1, align 4
ret void
}