[ARM] Fix an off-by-one error when restoring LR for 16-bit Thumb
The commit https://reviews.llvm.org/rL318143 computes incorrectly to offset to
restore LR from.
The number of tPOP operands is 2 (condition) + 2 (implicit def and use of SP) +
count of the popped registers. We need to load LR from just past the last
register, hence the correct offset should be either getNumOperands() - 4 and
getNumExplicitOperands() - 2 (multiplied by 4).
Differential revision: https://reviews.llvm.org/D40305
llvm-svn: 319014
diff --git a/llvm/test/CodeGen/ARM/v8m-tail-call.ll b/llvm/test/CodeGen/ARM/v8m-tail-call.ll
index 74a6c20..c369df0 100644
--- a/llvm/test/CodeGen/ARM/v8m-tail-call.ll
+++ b/llvm/test/CodeGen/ARM/v8m-tail-call.ll
@@ -8,7 +8,7 @@
%2 = tail call i32 @h0(i32 %1, i32 1, i32 2, i32 3)
ret i32 %2
; CHECK-LABEL: f0
-; CHECK: ldr [[POP:r[4567]]], [sp
+; CHECK: ldr [[POP:r[4567]]], [sp, #4]
; CHECK-NEXT: mov lr, [[POP]]
; CHECK-NEXT: pop {{.*}}[[POP]]
; CHECK-NEXT: add sp, #4
@@ -39,7 +39,7 @@
%11 = phi i32 [ %9, %8 ], [ -1, %5 ]
ret i32 %11
; CHECK-LABEL: f2
-; CHECK: ldr [[POP:r[4567]]], [sp
+; CHECK: ldr [[POP:r[4567]]], [sp, #12]
; CHECK-NEXT: mov lr, [[POP]]
; CHECK-NEXT: pop {{.*}}[[POP]]
; CHECK-NEXT: add sp, #4