llvm-project/llvm/test/Transforms/ScalarRepl/phi-select.ll

154 lines
4.1 KiB
LLVM

; RUN: opt %s -scalarrepl -S | FileCheck %s
; Test promotion of allocas that have phis and select users.
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
target triple = "x86_64-apple-darwin10.2"
%struct.X = type { i32 }
%PairTy = type {i32, i32}
; CHECK: @test1
; CHECK: %a.0 = alloca i32
; CHECK: %b.0 = alloca i32
define i32 @test1(i32 %x) nounwind readnone ssp {
entry:
%a = alloca %struct.X, align 8 ; <%struct.X*> [#uses=2]
%b = alloca %struct.X, align 8 ; <%struct.X*> [#uses=2]
%0 = getelementptr inbounds %struct.X* %a, i64 0, i32 0 ; <i32*> [#uses=1]
store i32 1, i32* %0, align 8
%1 = getelementptr inbounds %struct.X* %b, i64 0, i32 0 ; <i32*> [#uses=1]
store i32 2, i32* %1, align 8
%2 = icmp eq i32 %x, 0 ; <i1> [#uses=1]
%p.0 = select i1 %2, %struct.X* %b, %struct.X* %a ; <%struct.X*> [#uses=1]
%3 = getelementptr inbounds %struct.X* %p.0, i64 0, i32 0 ; <i32*> [#uses=1]
%4 = load i32* %3, align 8 ; <i32> [#uses=1]
ret i32 %4
}
; CHECK: @test2
; CHECK: %X.ld = phi i32 [ 1, %entry ], [ 2, %T ]
; CHECK-NEXT: ret i32 %X.ld
define i32 @test2(i1 %c) {
entry:
%A = alloca {i32, i32}
%B = getelementptr {i32, i32}* %A, i32 0, i32 0
store i32 1, i32* %B
br i1 %c, label %T, label %F
T:
%C = getelementptr {i32, i32}* %A, i32 0, i32 1
store i32 2, i32* %C
br label %F
F:
%X = phi i32* [%B, %entry], [%C, %T]
%Q = load i32* %X
ret i32 %Q
}
; CHECK: @test3
; CHECK-NEXT: %Q = select i1 %c, i32 1, i32 2
; CHECK-NEXT: ret i32 %Q
; rdar://8904039
define i32 @test3(i1 %c) {
%A = alloca {i32, i32}
%B = getelementptr {i32, i32}* %A, i32 0, i32 0
store i32 1, i32* %B
%C = getelementptr {i32, i32}* %A, i32 0, i32 1
store i32 2, i32* %C
%X = select i1 %c, i32* %B, i32* %C
%Q = load i32* %X
ret i32 %Q
}
;; We can't scalarize this, a use of the select is not an element access.
define i64 @test4(i1 %c) {
entry:
%A = alloca %PairTy
; CHECK: @test4
; CHECK: %A = alloca %PairTy
%B = getelementptr %PairTy* %A, i32 0, i32 0
store i32 1, i32* %B
%C = getelementptr %PairTy* %A, i32 0, i32 1
store i32 2, i32* %B
%X = select i1 %c, i32* %B, i32* %C
%Y = bitcast i32* %X to i64*
%Q = load i64* %Y
ret i64 %Q
}
;;
;; Tests for promoting allocas used by selects.
;; rdar://7339113
;;
define i32 @test5(i32 *%P) nounwind readnone ssp {
entry:
%b = alloca i32, align 8
store i32 2, i32* %b, align 8
;; Select on constant condition should be folded.
%p.0 = select i1 false, i32* %b, i32* %P
store i32 123, i32* %p.0
%r = load i32* %b, align 8
ret i32 %r
; CHECK: @test5
; CHECK: store i32 123, i32* %P
; CHECK: ret i32 2
}
define i32 @test6(i32 %x, i1 %c) nounwind readnone ssp {
%a = alloca i32, align 8
%b = alloca i32, align 8
store i32 1, i32* %a, align 8
store i32 2, i32* %b, align 8
%p.0 = select i1 %c, i32* %b, i32* %a
%r = load i32* %p.0, align 8
ret i32 %r
; CHECK: @test6
; CHECK-NEXT: %r = select i1 %c, i32 2, i32 1
; CHECK-NEXT: ret i32 %r
}
; Verify that the loads happen where the loads are, not where the select is.
define i32 @test7(i32 %x, i1 %c) nounwind readnone ssp {
%a = alloca i32, align 8
%b = alloca i32, align 8
store i32 1, i32* %a
store i32 2, i32* %b
%p.0 = select i1 %c, i32* %b, i32* %a
store i32 0, i32* %a
%r = load i32* %p.0, align 8
ret i32 %r
; CHECK: @test7
; CHECK-NOT: alloca i32
; CHECK: %r = select i1 %c, i32 2, i32 0
; CHECK: ret i32 %r
}
;; Promote allocs that are PHI'd together by moving the loads.
define i32 @test8(i32 %x) nounwind readnone ssp {
; CHECK: @test8
; CHECK-NOT: load i32
; CHECK-NOT: store i32
; CHECK: %p.0.ld = phi i32 [ 2, %entry ], [ 1, %T ]
; CHECK-NEXT: ret i32 %p.0.ld
entry:
%a = alloca i32, align 8
%b = alloca i32, align 8
store i32 1, i32* %a, align 8
store i32 2, i32* %b, align 8
%c = icmp eq i32 %x, 0
br i1 %c, label %T, label %Cont
T:
br label %Cont
Cont:
%p.0 = phi i32* [%b, %entry],[%a, %T]
%r = load i32* %p.0, align 8
ret i32 %r
}