ComputeKnownBits: be a bit smarter about ADDs
If our two inputs have known top-zero bit counts M and N, we trivially
know that the output cannot have any bits set in the top (min(M, N)-1)
bits, since nothing could carry past that point.
llvm-svn: 241927
diff --git a/llvm/test/CodeGen/AArch64/aarch64-dynamic-stack-layout.ll b/llvm/test/CodeGen/AArch64/aarch64-dynamic-stack-layout.ll
index a31c66b..f33211e 100644
--- a/llvm/test/CodeGen/AArch64/aarch64-dynamic-stack-layout.ll
+++ b/llvm/test/CodeGen/AArch64/aarch64-dynamic-stack-layout.ll
@@ -255,7 +255,7 @@
; CHECK: ubfx x9, x0, #0, #32
; CHECK: lsl x9, x9, #2
; CHECK: add x9, x9, #15
-; CHECK: and x9, x9, #0xfffffffffffffff0
+; CHECK: and x9, x9, #0x7fffffff0
; CHECK: mov x10, sp
; CHECK: sub x[[VLASPTMP:[0-9]+]], x10, x9
; CHECK: mov sp, x[[VLASPTMP]]
@@ -302,7 +302,7 @@
; CHECK: ubfx x9, x0, #0, #32
; CHECK: lsl x9, x9, #2
; CHECK: add x9, x9, #15
-; CHECK: and x9, x9, #0xfffffffffffffff0
+; CHECK: and x9, x9, #0x7fffffff0
; CHECK: mov x10, sp
; CHECK: sub x[[VLASPTMP:[0-9]+]], x10, x9
; CHECK: mov sp, x[[VLASPTMP]]
@@ -364,7 +364,7 @@
; CHECK: ubfx x9, x0, #0, #32
; CHECK: lsl x9, x9, #2
; CHECK: add x9, x9, #15
-; CHECK: and x9, x9, #0xfffffffffffffff0
+; CHECK: and x9, x9, #0x7fffffff0
; CHECK: mov x10, sp
; CHECK: sub x[[VLASPTMP:[0-9]+]], x10, x9
; CHECK: mov sp, x[[VLASPTMP]]
@@ -417,7 +417,7 @@
; CHECK: ubfx x9, x0, #0, #32
; CHECK: lsl x9, x9, #2
; CHECK: add x9, x9, #15
-; CHECK: and x9, x9, #0xfffffffffffffff0
+; CHECK: and x9, x9, #0x7fffffff0
; CHECK: mov x10, sp
; CHECK: sub x[[VLASPTMP:[0-9]+]], x10, x9
; CHECK: mov sp, x[[VLASPTMP]]
@@ -468,7 +468,7 @@
; CHECK: ubfx x9, x0, #0, #32
; CHECK: lsl x9, x9, #2
; CHECK: add x9, x9, #15
-; CHECK: and x9, x9, #0xfffffffffffffff0
+; CHECK: and x9, x9, #0x7fffffff0
; CHECK: mov x10, sp
; CHECK: sub x[[VLASPTMP:[0-9]+]], x10, x9
; CHECK: mov sp, x[[VLASPTMP]]