YouCompleteMe/cpp/llvm/test/Transforms/InstCombine/cast_ptr.ll
2012-07-05 17:51:06 -07:00

80 lines
2.3 KiB
LLVM

; Tests to make sure elimination of casts is working correctly
; RUN: opt < %s -instcombine -S | FileCheck %s
target datalayout = "p:32:32"
; This shouldn't convert to getelementptr because the relationship
; between the arithmetic and the layout of allocated memory is
; entirely unknown.
; CHECK: @test1
; CHECK: ptrtoint
; CHECK: add
; CHECK: inttoptr
define i8* @test1(i8* %t) {
%tmpc = ptrtoint i8* %t to i32 ; <i32> [#uses=1]
%tmpa = add i32 %tmpc, 32 ; <i32> [#uses=1]
%tv = inttoptr i32 %tmpa to i8* ; <i8*> [#uses=1]
ret i8* %tv
}
; These casts should be folded away.
; CHECK: @test2
; CHECK: icmp eq i8* %a, %b
define i1 @test2(i8* %a, i8* %b) {
%tmpa = ptrtoint i8* %a to i32 ; <i32> [#uses=1]
%tmpb = ptrtoint i8* %b to i32 ; <i32> [#uses=1]
%r = icmp eq i32 %tmpa, %tmpb ; <i1> [#uses=1]
ret i1 %r
}
; These casts should also be folded away.
; CHECK: @test3
; CHECK: icmp eq i8* %a, @global
@global = global i8 0
define i1 @test3(i8* %a) {
%tmpa = ptrtoint i8* %a to i32
%r = icmp eq i32 %tmpa, ptrtoint (i8* @global to i32)
ret i1 %r
}
define i1 @test4(i32 %A) {
%B = inttoptr i32 %A to i8*
%C = icmp eq i8* %B, null
ret i1 %C
; CHECK: @test4
; CHECK-NEXT: %C = icmp eq i32 %A, 0
; CHECK-NEXT: ret i1 %C
}
; Pulling the cast out of the load allows us to eliminate the load, and then
; the whole array.
%op = type { float }
%unop = type { i32 }
@Array = internal constant [1 x %op* (%op*)*] [ %op* (%op*)* @foo ] ; <[1 x %op* (%op*)*]*> [#uses=1]
declare %op* @foo(%op* %X)
define %unop* @test5(%op* %O) {
%tmp = load %unop* (%op*)** bitcast ([1 x %op* (%op*)*]* @Array to %unop* (%op*)**); <%unop* (%op*)*> [#uses=1]
%tmp.2 = call %unop* %tmp( %op* %O ) ; <%unop*> [#uses=1]
ret %unop* %tmp.2
; CHECK: @test5
; CHECK: call %op* @foo(%op* %O)
}
; InstCombine can not 'load (cast P)' -> cast (load P)' if the cast changes
; the address space.
define i8 @test6(i8 addrspace(1)* %source) {
entry:
%arrayidx223 = bitcast i8 addrspace(1)* %source to i8*
%tmp4 = load i8* %arrayidx223
ret i8 %tmp4
; CHECK: @test6
; CHECK: load i8* %arrayidx223
}