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llvm-project/llvm/test/Transforms/ArgumentPromotion/sret.ll

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ArgumentPromotion: Drop sret attribute on functions that are only called directly. If the first argument to a function is a 'this' argument and the second has the sret attribute, the ArgumentPromotion pass may promote the 'this' argument to more than one argument, violating the IR constraint that 'sret' may only be applied to the first or second argument. Although this IR constraint is arguably unnecessary, it highlighted the fact that ArgPromotion does not need to preserve this attribute. Dropping the attribute reduces register pressure in the backend by avoiding the register copy required by sret. Because sret implies noalias, we also replace the former with the latter. Differential Revision: http://reviews.llvm.org/D10353 llvm-svn: 239488
2015-06-11 05:14:34 +08:00
; RUN: opt < %s -argpromotion -S | FileCheck %s
[PM] Port ArgumentPromotion to the new pass manager. Now that the call graph supports efficient replacement of a function and spurious reference edges, we can port ArgumentPromotion to the new pass manager very easily. The old PM-specific bits are sunk into callbacks that the new PM simply doesn't use. Unlike the old PM, the new PM simply does argument promotion and afterward does the update to LCG reflecting the promoted function. Differential Revision: https://reviews.llvm.org/D29580 llvm-svn: 294667
2017-02-10 07:46:27 +08:00
; RUN: opt < %s -passes=argpromotion -S | FileCheck %s
ArgumentPromotion: Drop sret attribute on functions that are only called directly. If the first argument to a function is a 'this' argument and the second has the sret attribute, the ArgumentPromotion pass may promote the 'this' argument to more than one argument, violating the IR constraint that 'sret' may only be applied to the first or second argument. Although this IR constraint is arguably unnecessary, it highlighted the fact that ArgPromotion does not need to preserve this attribute. Dropping the attribute reduces register pressure in the backend by avoiding the register copy required by sret. Because sret implies noalias, we also replace the former with the latter. Differential Revision: http://reviews.llvm.org/D10353 llvm-svn: 239488
2015-06-11 05:14:34 +08:00
target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-pc-windows-msvc"
; CHECK: define internal void @add(i32 %[[THIS1:.*]], i32 %[[THIS2:.*]], i32* noalias %[[SR:.*]])
define internal void @add({i32, i32}* %this, i32* sret %r) {
%ap = getelementptr {i32, i32}, {i32, i32}* %this, i32 0, i32 0
%bp = getelementptr {i32, i32}, {i32, i32}* %this, i32 0, i32 1
%a = load i32, i32* %ap
%b = load i32, i32* %bp
; CHECK: %[[AB:.*]] = add i32 %[[THIS1]], %[[THIS2]]
%ab = add i32 %a, %b
; CHECK: store i32 %[[AB]], i32* %[[SR]]
store i32 %ab, i32* %r
ret void
}
; CHECK: define void @f()
define void @f() {
; CHECK: %[[R:.*]] = alloca i32
%r = alloca i32
%pair = alloca {i32, i32}
; CHECK: call void @add(i32 %{{.*}}, i32 %{{.*}}, i32* noalias %[[R]])
call void @add({i32, i32}* %pair, i32* sret %r)
ret void
}