Add "sub immediate" instruction to the ARM integrated assembler.

tests_lit/assembler/arm32/sub.ll

Index: tests_lit/assembler/arm32/sub.ll
diff --git a/tests_lit/assembler/arm32/add.ll b/tests_lit/assembler/arm32/sub.ll
similarity index 56%
copy from tests_lit/assembler/arm32/add.ll
copy to tests_lit/assembler/arm32/sub.ll
index 656137ca509094baa61975f542b81722bc91c7fd..e3193330b4216758b0c53e39ebf9c7101eb18da9 100644
--- a/tests_lit/assembler/arm32/add.ll
+++ b/tests_lit/assembler/arm32/sub.ll
@@ -1,5 +1,5 @@
-; Show that we know how to translate add.
-; TODO(kschimpf) Currently only know how to test add 1 to R0.
+; Show that we know how to translate instruction sub.
+; TODO(kschimpf) Currently only know how to test subtract 1 from R0.
 
 ; NOTE: We use -O2 to get rid of memory stores.
 
@@ -8,18 +8,18 @@
 ; RUN: %p2i --filetype=iasm -i %s --target=arm32 --args -O2 \
 ; RUN:   | FileCheck %s --check-prefix=IASM
 
-define internal i32 @add1ToR0(i32 %p) {
-  %v = add i32 %p, 1
+define internal i32 @sub1FromR0(i32 %p) {
+  %v = sub i32 %p, 1
   ret i32 %v
 }
 
-; ASM-LABEL: add1ToR0:
-; ASM:	add	r0, r0, #1
+; ASM-LABEL: sub1FromR0:
+; ASM:	sub	r0, r0, #1
 ; ASM:	bx	lr
 
-; IASM-LABEL: add1ToR0:
+; IASM-LABEL: sub1FromR0:
 ; IASM:	     .byte 0x1
 ; IASM-NEXT: .byte 0x0
-; IASM-NEXT: .byte 0x80
+; IASM-NEXT: .byte 0x40
 ; IASM-NEXT: .byte 0xe2