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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64093 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2009-02-08 20:44:19 +00:00
parent 4a2f112a5c
commit be685cc72a
1 changed files with 31 additions and 0 deletions
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31
lib/Target/X86/README.txt
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@ -1831,3 +1831,34 @@ unsigned long f2(struct s2 x) {
//===---------------------------------------------------------------------===//
We currently compile this:
define i32 @func1(i32 %v1, i32 %v2) nounwind {
entry:
%t = call {i32, i1} @llvm.sadd.with.overflow.i32(i32 %v1, i32 %v2)
%sum = extractvalue {i32, i1} %t, 0
%obit = extractvalue {i32, i1} %t, 1
br i1 %obit, label %overflow, label %normal
normal:
ret i32 %sum
overflow:
call void @llvm.trap()
unreachable
}
declare {i32, i1} @llvm.sadd.with.overflow.i32(i32, i32)
declare void @llvm.trap()
to:
_func1:
movl 4(%esp), %eax
addl 8(%esp), %eax
jo LBB1_2 ## overflow
LBB1_1: ## normal
ret
LBB1_2: ## overflow
ud2
it would be nice to produce "into" someday.
//===---------------------------------------------------------------------===//