For amusement, implement SADDO, SSUBO, UADDO, USUBO

for promoted integer types, eg: i16 on ppc-32, or
i24 on any platform.  Complete support for arbitrary
precision integers would require handling expanded
integer types, eg: i128, but I couldn't be bothered.

llvm-svn: 60834

1 files changed, 42 insertions, 0 deletions

diff --git a/llvm/test/CodeGen/Generic/add-with-overflow-24.ll b/llvm/test/CodeGen/Generic/add-with-overflow-24.ll
new file mode 100644
index 00000000000..debdeb25af0
--- /dev/null
+++ b/llvm/test/CodeGen/Generic/add-with-overflow-24.ll
@@ -0,0 +1,42 @@
+; RUN: llvm-as < %s | llc
+
+@ok = internal constant [4 x i8] c"%d\0A\00"
+@no = internal constant [4 x i8] c"no\0A\00"
+
+define i1 @func1(i24 signext %v1, i24 signext %v2) nounwind {
+entry:
+  %t = call {i24, i1} @llvm.sadd.with.overflow.i24(i24 %v1, i24 %v2)
+  %sum = extractvalue {i24, i1} %t, 0
+  %sum32 = sext i24 %sum to i32
+  %obit = extractvalue {i24, i1} %t, 1
+  br i1 %obit, label %overflow, label %normal
+
+normal:
+  %t1 = tail call i32 (i8*, ...)* @printf( i8* getelementptr ([4 x i8]* @ok, i32 0, i32 0), i32 %sum32 ) nounwind
+  ret i1 true
+
+overflow:
+  %t2 = tail call i32 (i8*, ...)* @printf( i8* getelementptr ([4 x i8]* @no, i32 0, i32 0) ) nounwind
+  ret i1 false
+}
+
+define i1 @func2(i24 zeroext %v1, i24 zeroext %v2) nounwind {
+entry:
+  %t = call {i24, i1} @llvm.uadd.with.overflow.i24(i24 %v1, i24 %v2)
+  %sum = extractvalue {i24, i1} %t, 0
+  %sum32 = zext i24 %sum to i32
+  %obit = extractvalue {i24, i1} %t, 1
+  br i1 %obit, label %carry, label %normal
+
+normal:
+  %t1 = tail call i32 (i8*, ...)* @printf( i8* getelementptr ([4 x i8]* @ok, i32 0, i32 0), i32 %sum32 ) nounwind
+  ret i1 true
+
+carry:
+  %t2 = tail call i32 (i8*, ...)* @printf( i8* getelementptr ([4 x i8]* @no, i32 0, i32 0) ) nounwind
+  ret i1 false
+}
+
+declare i32 @printf(i8*, ...) nounwind
+declare {i24, i1} @llvm.sadd.with.overflow.i24(i24, i24)
+declare {i24, i1} @llvm.uadd.with.overflow.i24(i24, i24)