1 files changed, 110 insertions, 1 deletions
diff --git a/llvm/test/CodeGen/AVR/calling-conv/c/stack.ll b/llvm/test/CodeGen/AVR/calling-conv/c/stack.ll
index 00ff7d1acd80..bfe01ede85a7 100644
--- a/llvm/test/CodeGen/AVR/calling-conv/c/stack.ll
+++ b/llvm/test/CodeGen/AVR/calling-conv/c/stack.ll
@@ -1,4 +1,4 @@
-; RUN: llc < %s -march=avr | FileCheck %s
+; RUN: llc -mtriple=avr < %s | FileCheck %s
 
 ; CHECK-LABEL: ret_void_args_i64_i64_i32
 define void @ret_void_args_i64_i64_i32(i64 %a, i64 %b, i32 %c) {
@@ -30,3 +30,112 @@ define void @ret_void_args_i64_i64_i32(i64 %a, i64 %b, i32 %c) {
   store volatile i32 %c, i32* inttoptr (i64 4 to i32*)
   ret void
 }
+
+; NOTE: All arguments are passed via the stack for varargs functions.
+; NOTE: Both %a & %b occupy a 1-byte stack slot.
+define i8 @foo0(i8 %a, i8 %b, ...) {
+; CHECK-LABEL: foo0:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    push r28
+; CHECK-NEXT:    push r29
+; CHECK-NEXT:    in r28, 61
+; CHECK-NEXT:    in r29, 62
+; CHECK-NEXT:    ldd r25, Y+6
+; CHECK-NEXT:    ldd r24, Y+5
+; CHECK-NEXT:    sub r24, r25
+; CHECK-NEXT:    pop r29
+; CHECK-NEXT:    pop r28
+; CHECK-NEXT:    ret
+  %c = sub i8 %a, %b
+  ret i8 %c
+}
+
+; NOTE: All arguments are passed via the stack since the argument %a is too large.
+define i8 @foo1([19 x i8] %a, i8 %b) {
+; CHECK-LABEL: foo1:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    push r28
+; CHECK-NEXT:    push r29
+; CHECK-NEXT:    in r28, 61
+; CHECK-NEXT:    in r29, 62
+; CHECK-NEXT:    ldd r25, Y+24
+; CHECK-NEXT:    ldd r24, Y+5
+; CHECK-NEXT:    sub r24, r25
+; CHECK-NEXT:    pop r29
+; CHECK-NEXT:    pop r28
+; CHECK-NEXT:    ret
+  %c = extractvalue [19 x i8] %a, 0
+  %d = sub i8 %c, %b
+  ret i8 %d
+}
+
+; NOTE: The argument %b is passed via the stack, since the argument %a costs
+; NOTE: total 18 registers though it is a 17-byte array.
+define i8 @foo2([17 x i8] %a, i8 %b) {
+; CHECK-LABEL: foo2:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    push r8
+; CHECK-NEXT:    push r28
+; CHECK-NEXT:    push r29
+; CHECK-NEXT:    in r28, 61
+; CHECK-NEXT:    in r29, 62
+; CHECK-NEXT:    ldd r24, Y+6
+; CHECK-NEXT:    sub r8, r24
+; CHECK-NEXT:    mov r24, r8
+; CHECK-NEXT:    pop r29
+; CHECK-NEXT:    pop r28
+; CHECK-NEXT:    pop r8
+; CHECK-NEXT:    ret
+  %c = extractvalue [17 x i8] %a, 0
+  %d = sub i8 %c, %b
+  ret i8 %d
+}
+
+; NOTE: Though %a costs 16 registers and 2 registers are vacant, the 4-byte
+; NOTE: %b has to be dropped to the stack.
+; NOTE: total 18 registers.
+define i32 @foo3([4 x i32] %a, i32 %b) {
+; CHECK-LABEL: foo3:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    push r28
+; CHECK-NEXT:    push r29
+; CHECK-NEXT:    in r28, 61
+; CHECK-NEXT:    in r29, 62
+; CHECK-NEXT:    ldd r22, Y+5
+; CHECK-NEXT:    ldd r23, Y+6
+; CHECK-NEXT:    ldd r24, Y+7
+; CHECK-NEXT:    ldd r25, Y+8
+; CHECK-NEXT:    sub r22, r10
+; CHECK-NEXT:    sbc r23, r11
+; CHECK-NEXT:    sbc r24, r12
+; CHECK-NEXT:    sbc r25, r13
+; CHECK-NEXT:    pop r29
+; CHECK-NEXT:    pop r28
+; CHECK-NEXT:    ret
+  %c = extractvalue [4 x i32] %a, 0
+  %d = sub nsw i32 %b, %c
+  ret i32 %d
+}
+
+; NOTE: Both %1 and %2 are passed via stack, and each has a 1-byte slot.
+define i8 @foo4([17 x i8] %0, i8 %1, i8 %2) {
+; CHECK-LABEL: foo4:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    push r8
+; CHECK-NEXT:    push r28
+; CHECK-NEXT:    push r29
+; CHECK-NEXT:    in r28, 61
+; CHECK-NEXT:    in r29, 62
+; CHECK-NEXT:    ldd r24, Y+6
+; CHECK-NEXT:    sub r8, r24
+; CHECK-NEXT:    ldd r24, Y+7
+; CHECK-NEXT:    add r24, r8
+; CHECK-NEXT:    pop r29
+; CHECK-NEXT:    pop r28
+; CHECK-NEXT:    pop r8
+; CHECK-NEXT:    ret
+  %4 = extractvalue [17 x i8] %0, 0
+  %5 = sub i8 %4, %1
+  %6 = add i8 %5, %2
+  ret i8 %6
+}