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; RUN: opt -instcombine -S %s | FileCheck %s
target datalayout = "p:32:32"
define i1 @alloca_argument_compare(i64* %arg) {
%alloc = alloca i64
%cmp = icmp eq i64* %arg, %alloc
ret i1 %cmp
; CHECK-LABEL: alloca_argument_compare
; CHECK: ret i1 false
}
define i1 @alloca_argument_compare_swapped(i64* %arg) {
%alloc = alloca i64
%cmp = icmp eq i64* %alloc, %arg
ret i1 %cmp
; CHECK-LABEL: alloca_argument_compare_swapped
; CHECK: ret i1 false
}
define i1 @alloca_argument_compare_ne(i64* %arg) {
%alloc = alloca i64
%cmp = icmp ne i64* %arg, %alloc
ret i1 %cmp
; CHECK-LABEL: alloca_argument_compare_ne
; CHECK: ret i1 true
}
define i1 @alloca_argument_compare_derived_ptrs(i64* %arg, i64 %x) {
%alloc = alloca i64, i64 8
%p = getelementptr i64, i64* %arg, i64 %x
%q = getelementptr i64, i64* %alloc, i64 3
%cmp = icmp eq i64* %p, %q
ret i1 %cmp
; CHECK-LABEL: alloca_argument_compare_derived_ptrs
; CHECK: ret i1 false
}
declare void @escape(i64*)
define i1 @alloca_argument_compare_escaped_alloca(i64* %arg) {
%alloc = alloca i64
call void @escape(i64* %alloc)
%cmp = icmp eq i64* %alloc, %arg
ret i1 %cmp
; CHECK-LABEL: alloca_argument_compare_escaped_alloca
; CHECK: %cmp = icmp eq i64* %alloc, %arg
; CHECK: ret i1 %cmp
}
declare void @check_compares(i1, i1)
define void @alloca_argument_compare_two_compares(i64* %p) {
%q = alloca i64, i64 8
%r = getelementptr i64, i64* %p, i64 1
%s = getelementptr i64, i64* %q, i64 2
%cmp1 = icmp eq i64* %p, %q
%cmp2 = icmp eq i64* %r, %s
call void @check_compares(i1 %cmp1, i1 %cmp2)
ret void
; We will only fold if there is a single cmp.
; CHECK-LABEL: alloca_argument_compare_two_compares
; CHECK: call void @check_compares(i1 %cmp1, i1 %cmp2)
}
define i1 @alloca_argument_compare_escaped_through_store(i64* %arg, i64** %ptr) {
%alloc = alloca i64
%cmp = icmp eq i64* %alloc, %arg
%p = getelementptr i64, i64* %alloc, i64 1
store i64* %p, i64** %ptr
ret i1 %cmp
; CHECK-LABEL: alloca_argument_compare_escaped_through_store
; CHECK: %cmp = icmp eq i64* %alloc, %arg
; CHECK: ret i1 %cmp
}
declare void @llvm.lifetime.start(i64, i8* nocapture)
declare void @llvm.lifetime.end(i64, i8* nocapture)
define i1 @alloca_argument_compare_benign_instrs(i8* %arg) {
%alloc = alloca i8
call void @llvm.lifetime.start(i64 1, i8* %alloc)
%cmp = icmp eq i8* %arg, %alloc
%x = load i8, i8* %arg
store i8 %x, i8* %alloc
call void @llvm.lifetime.end(i64 1, i8* %alloc)
ret i1 %cmp
; CHECK-LABEL: alloca_argument_compare_benign_instrs
; CHECK: ret i1 false
}
declare i64* @allocator()
define i1 @alloca_call_compare() {
%p = alloca i64
%q = call i64* @allocator()
%cmp = icmp eq i64* %p, %q
ret i1 %cmp
; CHECK-LABEL: alloca_call_compare
; CHECK: ret i1 false
}
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