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; RUN: opt < %s -instcombine -S | FileCheck %s
; PR1201
define i32 @main(i32 %argc, i8** %argv) {
; CHECK: @main
%c_19 = alloca i8*
%malloc_206 = tail call i8* @malloc(i32 mul (i32 ptrtoint (i8* getelementptr (i8* null, i32 1) to i32), i32 10))
store i8* %malloc_206, i8** %c_19
%tmp_207 = load i8** %c_19
tail call void @free(i8* %tmp_207)
ret i32 0
; CHECK-NEXT: ret i32 0
}
declare noalias i8* @calloc(i32, i32) nounwind
declare noalias i8* @malloc(i32)
declare void @free(i8*)
define i1 @foo() {
; CHECK: @foo
; CHECK-NEXT: ret i1 false
%m = call i8* @malloc(i32 1)
%z = icmp eq i8* %m, null
call void @free(i8* %m)
ret i1 %z
}
declare void @llvm.lifetime.start(i64, i8*)
declare void @llvm.lifetime.end(i64, i8*)
declare i64 @llvm.objectsize.i64(i8*, i1)
declare void @llvm.memcpy.p0i8.p0i8.i32(i8* nocapture, i8* nocapture, i32, i32, i1) nounwind
declare void @llvm.memmove.p0i8.p0i8.i32(i8* nocapture, i8* nocapture, i32, i32, i1) nounwind
declare void @llvm.memset.p0i8.i32(i8*, i8, i32, i32, i1) nounwind
define void @test3(i8* %src) {
; CHECK: @test3
; CHECK-NEXT: ret void
%a = call noalias i8* @malloc(i32 10)
call void @llvm.lifetime.start(i64 10, i8* %a)
call void @llvm.lifetime.end(i64 10, i8* %a)
%size = call i64 @llvm.objectsize.i64(i8* %a, i1 true)
store i8 42, i8* %a
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %a, i8* %src, i32 32, i32 1, i1 false)
call void @llvm.memmove.p0i8.p0i8.i32(i8* %a, i8* %src, i32 32, i32 1, i1 false)
call void @llvm.memset.p0i8.i32(i8* %a, i8 5, i32 32, i32 1, i1 false)
%alloc2 = call noalias i8* @calloc(i32 5, i32 7) nounwind
%z = icmp ne i8* %alloc2, null
ret void
}
;; This used to crash.
define void @test4() {
; CHECK: @test4
; CHECK-NEXT: ret void
%A = call i8* @malloc(i32 16000)
%B = bitcast i8* %A to double*
%C = bitcast double* %B to i8*
call void @free(i8* %C)
ret void
}
; CHECK: @test5
define void @test5(i8* %ptr, i8** %esc) {
; CHECK-NEXT: call i8* @malloc
; CHECK-NEXT: call i8* @malloc
; CHECK-NEXT: call i8* @malloc
; CHECK-NEXT: call i8* @malloc
; CHECK-NEXT: call i8* @malloc
; CHECK-NEXT: call i8* @malloc
; CHECK-NEXT: call i8* @malloc
; CHECK-NEXT: call void @llvm.memcpy
; CHECK-NEXT: call void @llvm.memmove
; CHECK-NEXT: store
; CHECK-NEXT: call void @llvm.memcpy
; CHECK-NEXT: call void @llvm.memmove
; CHECK-NEXT: call void @llvm.memset
; CHECK-NEXT: store volatile
; CHECK-NEXT: ret
%a = call i8* @malloc(i32 700)
%b = call i8* @malloc(i32 700)
%c = call i8* @malloc(i32 700)
%d = call i8* @malloc(i32 700)
%e = call i8* @malloc(i32 700)
%f = call i8* @malloc(i32 700)
%g = call i8* @malloc(i32 700)
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %ptr, i8* %a, i32 32, i32 1, i1 false)
call void @llvm.memmove.p0i8.p0i8.i32(i8* %ptr, i8* %b, i32 32, i32 1, i1 false)
store i8* %c, i8** %esc
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %d, i8* %ptr, i32 32, i32 1, i1 true)
call void @llvm.memmove.p0i8.p0i8.i32(i8* %e, i8* %ptr, i32 32, i32 1, i1 true)
call void @llvm.memset.p0i8.i32(i8* %f, i8 5, i32 32, i32 1, i1 true)
store volatile i8 4, i8* %g
ret void
}
;; When a basic block contains only a call to free and this block is accessed
;; through a test of the argument of free against null, move the call in the
;; predecessor block.
;; Using simplifycfg will remove the empty basic block and the branch operation
;; Then, performing a dead elimination will remove the comparison.
;; This is what happens with -O1 and upper.
; CHECK: @test6
define void @test6(i8* %foo) minsize {
; CHECK: %tobool = icmp eq i8* %foo, null
;; Call to free moved
; CHECK-NEXT: tail call void @free(i8* %foo)
; CHECK-NEXT: br i1 %tobool, label %if.end, label %if.then
; CHECK: if.then:
;; Block is now empty and may be simplified by simplifycfg
; CHECK-NEXT: br label %if.end
; CHECK: if.end:
; CHECK-NEXT: ret void
entry:
%tobool = icmp eq i8* %foo, null
br i1 %tobool, label %if.end, label %if.then
if.then: ; preds = %entry
tail call void @free(i8* %foo)
br label %if.end
if.end: ; preds = %entry, %if.then
ret void
}
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