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| ; RUN: llc -mtriple=thumbv6m-eabi -frame-pointer=none %s -o - | FileCheck %s
; struct S { int x[128]; } s;
; int f(int *, int, int, int, struct S);
; int g(int *, int, int, int, int, int);
; int h(int *, int *, int *);
; int u(int *, int *, int *, struct S, struct S);
%struct.S = type { [128 x i32] }
%struct.__va_list = type { i8* }
@s = common dso_local global %struct.S zeroinitializer, align 4
declare void @llvm.va_start(i8*)
declare dso_local i32 @g(i32*, i32, i32, i32, i32, i32) local_unnamed_addr
declare dso_local i32 @f(i32*, i32, i32, i32, %struct.S* byval align 4) local_unnamed_addr
declare dso_local i32 @h(i32*, i32*, i32*) local_unnamed_addr
declare dso_local i32 @u(i32*, i32*, i32*, %struct.S* byval align 4, %struct.S* byval align 4) local_unnamed_addr
;
; Test access to arguments, passed on stack (including varargs)
;
; Usual case, access via SP
; int test_args_sp(int a, int b, int c, int d, int e) {
; int v[4];
; return g(v, a, b, c, d, e);
; }
define dso_local i32 @test_args_sp(i32 %a, i32 %b, i32 %c, i32 %d, i32 %e) local_unnamed_addr {
entry:
%v = alloca [4 x i32], align 4
%0 = bitcast [4 x i32]* %v to i8*
%arraydecay = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 0
%call = call i32 @g(i32* nonnull %arraydecay, i32 %a, i32 %b, i32 %c, i32 %d, i32 %e)
ret i32 %call
}
; CHECK-LABEL: test_args_sp
; Load `e`
; CHECK: ldr r0, [sp, #32]
; CHECK-NEXT: str r3, [sp]
; Pass `e` on stack
; CHECK-NEXT: str r0, [sp, #4]
; CHECK: bl g
; int test_varargs_sp(int a, ...) {
; int v[4];
; __builtin_va_list ap;
; __builtin_va_start(ap, a);
; return g(v, a, 0, 0, 0, 0);
; }
define dso_local i32 @test_varargs_sp(i32 %a, ...) local_unnamed_addr {
entry:
%v = alloca [4 x i32], align 4
%ap = alloca %struct.__va_list, align 4
%0 = bitcast [4 x i32]* %v to i8*
%1 = bitcast %struct.__va_list* %ap to i8*
call void @llvm.va_start(i8* nonnull %1)
%arraydecay = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 0
%call = call i32 @g(i32* nonnull %arraydecay, i32 %a, i32 0, i32 0, i32 0, i32 0)
ret i32 %call
}
; CHECK-LABEL: test_varargs_sp
; Three incoming varargs in registers
; CHECK: sub sp, #12
; CHECK: sub sp, #28
; Incoming arguments area is accessed via SP
; CHECK: add r0, sp, #36
; CHECK: stm r0!, {r1, r2, r3}
; Re-aligned stack, access via FP
; int test_args_realign(int a, int b, int c, int d, int e) {
; __attribute__((aligned(16))) int v[4];
; return g(v, a, b, c, d, e);
; }
; Function Attrs: nounwind
define dso_local i32 @test_args_realign(i32 %a, i32 %b, i32 %c, i32 %d, i32 %e) local_unnamed_addr {
entry:
%v = alloca [4 x i32], align 16
%0 = bitcast [4 x i32]* %v to i8*
%arraydecay = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 0
%call = call i32 @g(i32* nonnull %arraydecay, i32 %a, i32 %b, i32 %c, i32 %d, i32 %e)
ret i32 %call
}
; CHECK-LABEL: test_args_realign
; Setup frame pointer
; CHECK: add r7, sp, #8
; Align stack
; CHECK: mov r4, sp
; CHECK-NEXT: lsrs r4, r4, #4
; CHECK-NEXT: lsls r4, r4, #4
; CHECK-NEXT: mov sp, r4
; Load `e` via FP
; CHECK: ldr r0, [r7, #8]
; CHECK-NEXT: str r3, [sp]
; Pass `e` as argument
; CHECK-NEXT: str r0, [sp, #4]
; CHECK: bl g
; int test_varargs_realign(int a, ...) {
; __attribute__((aligned(16))) int v[4];
; __builtin_va_list ap;
; __builtin_va_start(ap, a);
; return g(v, a, 0, 0, 0, 0);
; }
define dso_local i32 @test_varargs_realign(i32 %a, ...) local_unnamed_addr {
entry:
%v = alloca [4 x i32], align 16
%ap = alloca %struct.__va_list, align 4
%0 = bitcast [4 x i32]* %v to i8*
%1 = bitcast %struct.__va_list* %ap to i8*
call void @llvm.va_start(i8* nonnull %1)
%arraydecay = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 0
%call = call i32 @g(i32* nonnull %arraydecay, i32 %a, i32 0, i32 0, i32 0, i32 0)
ret i32 %call
}
; CHECK-LABEL: test_varargs_realign
; Three incoming register varargs
; CHECK: sub sp, #12
; Setup frame pointer
; CHECK: add r7, sp, #8
; Align stack
; CHECK: mov r4, sp
; CHECK-NEXT: lsrs r4, r4, #4
; CHECK-NEXT: lsls r4, r4, #4
; CHECK-NEXT: mov sp, r4
; Incoming register varargs stored via FP
; CHECK: mov r0, r7
; CHECK-NEXT: adds r0, #8
; CHECK-NEXT: stm r0!, {r1, r2, r3}
; VLAs present, access via FP
; int test_args_vla(int a, int b, int c, int d, int e) {
; int v[a];
; return g(v, a, b, c, d, e);
; }
define dso_local i32 @test_args_vla(i32 %a, i32 %b, i32 %c, i32 %d, i32 %e) local_unnamed_addr {
entry:
%vla = alloca i32, i32 %a, align 4
%call = call i32 @g(i32* nonnull %vla, i32 %a, i32 %b, i32 %c, i32 %d, i32 %e)
ret i32 %call
}
; CHECK-LABEL: test_args_vla
; Setup frame pointer
; CHECK: add r7, sp, #12
; Allocate outgoing stack arguments space
; CHECK: sub sp, #4
; Load `e` via FP
; CHECK: ldr r5, [r7, #8]
; Pass `d` and `e` as arguments
; CHECK-NEXT: str r3, [sp]
; CHECK-NEXT: str r5, [sp, #4]
; CHECK: bl g
; int test_varargs_vla(int a, ...) {
; int v[a];
; __builtin_va_list ap;
; __builtin_va_start(ap, a);
; return g(v, a, 0, 0, 0, 0);
; }
define dso_local i32 @test_varargs_vla(i32 %a, ...) local_unnamed_addr {
entry:
%ap = alloca %struct.__va_list, align 4
%vla = alloca i32, i32 %a, align 4
%0 = bitcast %struct.__va_list* %ap to i8*
call void @llvm.va_start(i8* nonnull %0)
%call = call i32 @g(i32* nonnull %vla, i32 %a, i32 0, i32 0, i32 0, i32 0)
ret i32 %call
}
; CHECK-LABEL: test_varargs_vla
; Three incoming register varargs
; CHECK: sub sp, #12
; Setup frame pointer
; CHECK: add r7, sp, #8
; Register varargs stored via FP
; CHECK-DAG: str r3, [r7, #16]
; CHECK-DAG: str r2, [r7, #12]
; CHECK-DAG: str r1, [r7, #8]
; Moving SP, access via SP
; int test_args_moving_sp(int a, int b, int c, int d, int e) {
; int v[4];
; return f(v, a, b + c + d, e, s) + h(v, v+1, v+2);
; }
define dso_local i32 @test_args_moving_sp(i32 %a, i32 %b, i32 %c, i32 %d, i32 %e) local_unnamed_addr {
entry:
%v = alloca [4 x i32], align 4
%0 = bitcast [4 x i32]* %v to i8*
%arraydecay = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 0
%add = add nsw i32 %c, %b
%add1 = add nsw i32 %add, %d
%call = call i32 @f(i32* nonnull %arraydecay, i32 %a, i32 %add1, i32 %e, %struct.S* byval nonnull align 4 @s)
%add.ptr = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 1
%add.ptr5 = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 2
%call6 = call i32 @h(i32* nonnull %arraydecay, i32* nonnull %add.ptr, i32* nonnull %add.ptr5)
%add7 = add nsw i32 %call6, %call
ret i32 %add7
}
; CHECK-LABEL: test_args_moving_sp
; 20 bytes callee-saved area
; CHECK: push {r4, r5, r6, r7, lr}
; 20 bytes locals
; CHECK: sub sp, #20
; Setup base pointer
; CHECK: mov r6, sp
; Allocate outgoing arguments space
; CHECK: sub sp, #508
; CHECK: sub sp, #4
; Load `e` via BP, 40 = 20 + 20
; CHECK: ldr r3, [r6, #40]
; CHECK: bl f
; Stack restored before next call
; CHECK-NEXT: add sp, #508
; CHECK-NEXT: add sp, #4
; CHECK: bl h
; int test_varargs_moving_sp(int a, ...) {
; int v[4];
; __builtin_va_list ap;
; __builtin_va_start(ap, a);
; return f(v, a, 0, 0, s) + h(v, v+1, v+2);
; }
define dso_local i32 @test_varargs_moving_sp(i32 %a, ...) local_unnamed_addr {
entry:
%v = alloca [4 x i32], align 4
%ap = alloca %struct.__va_list, align 4
%0 = bitcast [4 x i32]* %v to i8*
%1 = bitcast %struct.__va_list* %ap to i8*
call void @llvm.va_start(i8* nonnull %1)
%arraydecay = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 0
%call = call i32 @f(i32* nonnull %arraydecay, i32 %a, i32 0, i32 0, %struct.S* byval nonnull align 4 @s)
%add.ptr = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 1
%add.ptr5 = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 2
%call6 = call i32 @h(i32* nonnull %arraydecay, i32* nonnull %add.ptr, i32* nonnull %add.ptr5)
%add = add nsw i32 %call6, %call
ret i32 %add
}
; CHECK-LABEL: test_varargs_moving_sp
; Three incoming register varargs
; CHECK: sub sp, #12
; 16 bytes callee-saves
; CHECK: push {r4, r5, r6, lr}
; 20 bytes locals
; CHECK: sub sp, #20
; Incoming varargs stored via BP, 36 = 20 + 16
; CHECK: mov r0, r6
; CHECK-NEXT: adds r0, #36
; CHECK-NEXT: stm r0!, {r1, r2, r3}
;
; Access to locals
;
; Usual case, access via SP.
; int test_local(int n) {
; int v[4];
; int x, y, z;
; h(&x, &y, &z);
; return g(v, x, y, z, 0, 0);
; }
define dso_local i32 @test_local(i32 %n) local_unnamed_addr {
entry:
%v = alloca [4 x i32], align 4
%x = alloca i32, align 4
%y = alloca i32, align 4
%z = alloca i32, align 4
%0 = bitcast [4 x i32]* %v to i8*
%1 = bitcast i32* %x to i8*
%2 = bitcast i32* %y to i8*
%3 = bitcast i32* %z to i8*
%call = call i32 @h(i32* nonnull %x, i32* nonnull %y, i32* nonnull %z)
%arraydecay = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 0
%4 = load i32, i32* %x, align 4
%5 = load i32, i32* %y, align 4
%6 = load i32, i32* %z, align 4
%call1 = call i32 @g(i32* nonnull %arraydecay, i32 %4, i32 %5, i32 %6, i32 0, i32 0)
ret i32 %call1
}
; CHECK-LABEL: test_local
; Arguments to `h` relative to SP
; CHECK: add r0, sp, #20
; CHECK-NEXT: add r1, sp, #16
; CHECK-NEXT: add r2, sp, #12
; CHECK-NEXT: bl h
; Load `x`, `y`, and `z` via SP
; CHECK: ldr r1, [sp, #20]
; CHECK-NEXT: ldr r2, [sp, #16]
; CHECK-NEXT: ldr r3, [sp, #12]
; CHECK: bl g
; Re-aligned stack, access via SP.
; int test_local_realign(int n) {
; __attribute__((aligned(16))) int v[4];
; int x, y, z;
; h(&x, &y, &z);
; return g(v, x, y, z, 0, 0);
; }
define dso_local i32 @test_local_realign(i32 %n) local_unnamed_addr {
entry:
%v = alloca [4 x i32], align 16
%x = alloca i32, align 4
%y = alloca i32, align 4
%z = alloca i32, align 4
%0 = bitcast [4 x i32]* %v to i8*
%1 = bitcast i32* %x to i8*
%2 = bitcast i32* %y to i8*
%3 = bitcast i32* %z to i8*
%call = call i32 @h(i32* nonnull %x, i32* nonnull %y, i32* nonnull %z)
%arraydecay = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 0
%4 = load i32, i32* %x, align 4
%5 = load i32, i32* %y, align 4
%6 = load i32, i32* %z, align 4
%call1 = call i32 @g(i32* nonnull %arraydecay, i32 %4, i32 %5, i32 %6, i32 0, i32 0)
ret i32 %call1
}
; CHECK-LABEL: test_local_realign
; Setup frame pointer
; CHECK: add r7, sp, #8
; Re-align stack
; CHECK: mov r4, sp
; CHECK-NEXT: lsrs r4, r4, #4
; CHECK-NEXT: lsls r4, r4, #4
; CHECK-NEXT: mov sp, r4
; Arguments to `h` computed relative to SP
; CHECK: add r0, sp, #28
; CHECK-NEXT: add r1, sp, #24
; CHECK-NEXT: add r2, sp, #20
; CHECK-NEXT: bl h
; Load `x`, `y`, and `z` via SP for passing to `g`
; CHECK: ldr r1, [sp, #28]
; CHECK-NEXT: ldr r2, [sp, #24]
; CHECK-NEXT: ldr r3, [sp, #20]
; CHECK: bl g
; VLAs, access via BP.
; int test_local_vla(int n) {
; int v[n];
; int x, y, z;
; h(&x, &y, &z);
; return g(v, x, y, z, 0, 0);
; }
define dso_local i32 @test_local_vla(i32 %n) local_unnamed_addr {
entry:
%x = alloca i32, align 4
%y = alloca i32, align 4
%z = alloca i32, align 4
%vla = alloca i32, i32 %n, align 4
%0 = bitcast i32* %x to i8*
%1 = bitcast i32* %y to i8*
%2 = bitcast i32* %z to i8*
%call = call i32 @h(i32* nonnull %x, i32* nonnull %y, i32* nonnull %z)
%3 = load i32, i32* %x, align 4
%4 = load i32, i32* %y, align 4
%5 = load i32, i32* %z, align 4
%call1 = call i32 @g(i32* nonnull %vla, i32 %3, i32 %4, i32 %5, i32 0, i32 0)
ret i32 %call1
}
; CHECK-LABEL: test_local_vla
; Setup frame pointer
; CHECK: add r7, sp, #12
; Setup base pointer
; CHECK: mov r6, sp
; CHECK: mov r5, r6
; Arguments to `h` compute relative to BP
; CHECK: adds r0, r6, #7
; CHECK-NEXT: adds r0, #1
; CHECK-NEXT: adds r1, r6, #4
; CHECK-NEXT: mov r2, r6
; CHECK-NEXT: bl h
; Load `x`, `y`, `z` via BP (r5 should still have the value of r6 from the move
; above)
; CHECK: ldr r3, [r5]
; CHECK-NEXT: ldr r2, [r5, #4]
; CHECK-NEXT: ldr r1, [r5, #8]
; CHECK: bl g
; Moving SP, access via SP.
; int test_local_moving_sp(int n) {
; int v[4];
; int x, y, z;
; return u(v, &x, &y, s, s) + u(v, &y, &z, s, s);
; }
define dso_local i32 @test_local_moving_sp(i32 %n) local_unnamed_addr {
entry:
%v = alloca [4 x i32], align 4
%x = alloca i32, align 4
%y = alloca i32, align 4
%z = alloca i32, align 4
%0 = bitcast [4 x i32]* %v to i8*
%1 = bitcast i32* %x to i8*
%2 = bitcast i32* %y to i8*
%3 = bitcast i32* %z to i8*
%arraydecay = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 0
%call = call i32 @u(i32* nonnull %arraydecay, i32* nonnull %x, i32* nonnull %y, %struct.S* byval nonnull align 4 @s, %struct.S* byval nonnull align 4 @s)
%call2 = call i32 @u(i32* nonnull %arraydecay, i32* nonnull %y, i32* nonnull %z, %struct.S* byval nonnull align 4 @s, %struct.S* byval nonnull align 4 @s)
%add = add nsw i32 %call2, %call
ret i32 %add
}
; CHECK-LABEL: test_local_moving_sp
; Locals area
; CHECK: sub sp, #36
; Setup BP
; CHECK: mov r6, sp
; Outoging arguments
; CHECK: sub sp, #508
; CHECK-NEXT: sub sp, #508
; CHECK-NEXT: sub sp, #8
; Argument addresses computed relative to BP
; CHECK: adds r0, r6, #7
; CHECK-NEXT: adds r0, #13
; CHECK: adds r1, r6, #7
; CHECK-NEXT: adds r1, #9
; CHECK: adds r5, r6, #7
; CHECK-NEXT: adds r5, #5
; CHECK: bl u
; Stack restored before next call
; CHECK: add sp, #508
; CHECK-NEXT: add sp, #508
; CHECK-NEXT: add sp, #8
; CHECK: bl u
|