llvm/test/CodeGen/Generic/add-with-overflow-128.ll
Eli Friedman 268637ed0f Implement expansion in type legalization for add/sub with overflow. The
expansion is the same as that used by LegalizeDAG.

The resulting code sucks in terms of performance/codesize on x86-32 for a
64-bit operation; I haven't looked into whether different expansions might be
better in general.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@105378 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-03 03:49:50 +00:00

43 lines
1.4 KiB
LLVM

; RUN: llc < %s
@ok = internal constant [4 x i8] c"%d\0A\00"
@no = internal constant [4 x i8] c"no\0A\00"
define i1 @func1(i128 signext %v1, i128 signext %v2) nounwind {
entry:
%t = call {i128, i1} @llvm.sadd.with.overflow.i128(i128 %v1, i128 %v2)
%sum = extractvalue {i128, i1} %t, 0
%sum32 = trunc i128 %sum to i32
%obit = extractvalue {i128, 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(i128 zeroext %v1, i128 zeroext %v2) nounwind {
entry:
%t = call {i128, i1} @llvm.uadd.with.overflow.i128(i128 %v1, i128 %v2)
%sum = extractvalue {i128, i1} %t, 0
%sum32 = trunc i128 %sum to i32
%obit = extractvalue {i128, 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 {i128, i1} @llvm.sadd.with.overflow.i128(i128, i128)
declare {i128, i1} @llvm.uadd.with.overflow.i128(i128, i128)