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|
; This test makes sure that these instructions are properly eliminated.
;
; RUN: opt < %s -instcombine -S | FileCheck %s
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"
define i32 @test1(i32 %A, i1 %b) {
BB0:
br i1 %b, label %BB1, label %BB2
BB1:
; Combine away one argument PHI nodes
%B = phi i32 [ %A, %BB0 ]
ret i32 %B
BB2:
ret i32 %A
; CHECK: @test1
; CHECK: BB1:
; CHECK-NEXT: ret i32 %A
}
define i32 @test2(i32 %A, i1 %b) {
BB0:
br i1 %b, label %BB1, label %BB2
BB1:
br label %BB2
BB2:
; Combine away PHI nodes with same values
%B = phi i32 [ %A, %BB0 ], [ %A, %BB1 ]
ret i32 %B
; CHECK: @test2
; CHECK: BB2:
; CHECK-NEXT: ret i32 %A
}
define i32 @test3(i32 %A, i1 %b) {
BB0:
br label %Loop
Loop:
; PHI has same value always.
%B = phi i32 [ %A, %BB0 ], [ %B, %Loop ]
br i1 %b, label %Loop, label %Exit
Exit:
ret i32 %B
; CHECK: @test3
; CHECK: Exit:
; CHECK-NEXT: ret i32 %A
}
define i32 @test4(i1 %b) {
BB0:
; Loop is unreachable
ret i32 7
Loop: ; preds = %L2, %Loop
; PHI has same value always.
%B = phi i32 [ %B, %L2 ], [ %B, %Loop ]
br i1 %b, label %L2, label %Loop
L2: ; preds = %Loop
br label %Loop
; CHECK: @test4
; CHECK: Loop:
; CHECK-NEXT: br i1 %b
}
define i32 @test5(i32 %A, i1 %b) {
BB0:
br label %Loop
Loop: ; preds = %Loop, %BB0
; PHI has same value always.
%B = phi i32 [ %A, %BB0 ], [ undef, %Loop ]
br i1 %b, label %Loop, label %Exit
Exit: ; preds = %Loop
ret i32 %B
; CHECK: @test5
; CHECK: Loop:
; CHECK-NEXT: br i1 %b
; CHECK: Exit:
; CHECK-NEXT: ret i32 %A
}
define i32 @test6(i16 %A, i1 %b) {
BB0:
%X = zext i16 %A to i32
br i1 %b, label %BB1, label %BB2
BB1:
%Y = zext i16 %A to i32
br label %BB2
BB2:
;; Suck casts into phi
%B = phi i32 [ %X, %BB0 ], [ %Y, %BB1 ]
ret i32 %B
; CHECK: @test6
; CHECK: BB2:
; CHECK: zext i16 %A to i32
; CHECK-NEXT: ret i32
}
define i32 @test7(i32 %A, i1 %b) {
BB0:
br label %Loop
Loop: ; preds = %Loop, %BB0
; PHI is dead.
%B = phi i32 [ %A, %BB0 ], [ %C, %Loop ]
%C = add i32 %B, 123
br i1 %b, label %Loop, label %Exit
Exit: ; preds = %Loop
ret i32 0
; CHECK: @test7
; CHECK: Loop:
; CHECK-NEXT: br i1 %b
}
define i32* @test8({ i32, i32 } *%A, i1 %b) {
BB0:
%X = getelementptr { i32, i32 } *%A, i32 0, i32 1
br i1 %b, label %BB1, label %BB2
BB1:
%Y = getelementptr { i32, i32 } *%A, i32 0, i32 1
br label %BB2
BB2:
;; Suck GEPs into phi
%B = phi i32* [ %X, %BB0 ], [ %Y, %BB1 ]
ret i32* %B
; CHECK: @test8
; CHECK-NOT: phi
; CHECK: BB2:
; CHECK-NEXT: %B = getelementptr
; CHECK-NEXT: ret i32* %B
}
define i32 @test9(i32* %A, i32* %B) {
entry:
%c = icmp eq i32* %A, null
br i1 %c, label %bb1, label %bb
bb:
%C = load i32* %B, align 1
br label %bb2
bb1:
%D = load i32* %A, align 1
br label %bb2
bb2:
%E = phi i32 [ %C, %bb ], [ %D, %bb1 ]
ret i32 %E
; CHECK: @test9
; CHECK: bb2:
; CHECK-NEXT: phi i32* [ %B, %bb ], [ %A, %bb1 ]
; CHECK-NEXT: %E = load i32* %{{[^,]*}}, align 1
; CHECK-NEXT: ret i32 %E
}
define i32 @test10(i32* %A, i32* %B) {
entry:
%c = icmp eq i32* %A, null
br i1 %c, label %bb1, label %bb
bb:
%C = load i32* %B, align 16
br label %bb2
bb1:
%D = load i32* %A, align 32
br label %bb2
bb2:
%E = phi i32 [ %C, %bb ], [ %D, %bb1 ]
ret i32 %E
; CHECK: @test10
; CHECK: bb2:
; CHECK-NEXT: phi i32* [ %B, %bb ], [ %A, %bb1 ]
; CHECK-NEXT: %E = load i32* %{{[^,]*}}, align 16
; CHECK-NEXT: ret i32 %E
}
; PR1777
declare i1 @test11a()
define i1 @test11() {
entry:
%a = alloca i32
%i = ptrtoint i32* %a to i32
%b = call i1 @test11a()
br i1 %b, label %one, label %two
one:
%x = phi i32 [%i, %entry], [%y, %two]
%c = call i1 @test11a()
br i1 %c, label %two, label %end
two:
%y = phi i32 [%i, %entry], [%x, %one]
%d = call i1 @test11a()
br i1 %d, label %one, label %end
end:
%f = phi i32 [ %x, %one], [%y, %two]
; Change the %f to %i, and the optimizer suddenly becomes a lot smarter
; even though %f must equal %i at this point
%g = inttoptr i32 %f to i32*
store i32 10, i32* %g
%z = call i1 @test11a()
ret i1 %z
; CHECK: @test11
; CHECK-NOT: phi i32
; CHECK: ret i1 %z
}
define i64 @test12(i1 %cond, i8* %Ptr, i64 %Val) {
entry:
%tmp41 = ptrtoint i8* %Ptr to i64
%tmp42 = zext i64 %tmp41 to i128
br i1 %cond, label %end, label %two
two:
%tmp36 = zext i64 %Val to i128 ; <i128> [#uses=1]
%tmp37 = shl i128 %tmp36, 64 ; <i128> [#uses=1]
%ins39 = or i128 %tmp42, %tmp37 ; <i128> [#uses=1]
br label %end
end:
%tmp869.0 = phi i128 [ %tmp42, %entry ], [ %ins39, %two ]
%tmp32 = trunc i128 %tmp869.0 to i64 ; <i64> [#uses=1]
%tmp29 = lshr i128 %tmp869.0, 64 ; <i128> [#uses=1]
%tmp30 = trunc i128 %tmp29 to i64 ; <i64> [#uses=1]
%tmp2 = add i64 %tmp32, %tmp30
ret i64 %tmp2
; CHECK: @test12
; CHECK-NOT: zext
; CHECK: end:
; CHECK-NEXT: phi i64 [ 0, %entry ], [ %Val, %two ]
; CHECK-NOT: phi
; CHECK: ret i64
}
declare void @test13f(double, i32)
define void @test13(i1 %cond, i32 %V1, double %Vald) {
entry:
%tmp42 = zext i32 %V1 to i128
br i1 %cond, label %end, label %two
two:
%Val = bitcast double %Vald to i64
%tmp36 = zext i64 %Val to i128 ; <i128> [#uses=1]
%tmp37 = shl i128 %tmp36, 64 ; <i128> [#uses=1]
%ins39 = or i128 %tmp42, %tmp37 ; <i128> [#uses=1]
br label %end
end:
%tmp869.0 = phi i128 [ %tmp42, %entry ], [ %ins39, %two ]
%tmp32 = trunc i128 %tmp869.0 to i32
%tmp29 = lshr i128 %tmp869.0, 64 ; <i128> [#uses=1]
%tmp30 = trunc i128 %tmp29 to i64 ; <i64> [#uses=1]
%tmp31 = bitcast i64 %tmp30 to double
call void @test13f(double %tmp31, i32 %tmp32)
ret void
; CHECK: @test13
; CHECK-NOT: zext
; CHECK: end:
; CHECK-NEXT: phi double [ 0.000000e+00, %entry ], [ %Vald, %two ]
; CHECK-NEXT: call void @test13f(double {{[^,]*}}, i32 %V1)
; CHECK: ret void
}
define i640 @test14a(i320 %A, i320 %B, i1 %b1) {
BB0:
%a = zext i320 %A to i640
%b = zext i320 %B to i640
br label %Loop
Loop:
%C = phi i640 [ %a, %BB0 ], [ %b, %Loop ]
br i1 %b1, label %Loop, label %Exit
Exit: ; preds = %Loop
ret i640 %C
; CHECK: @test14a
; CHECK: Loop:
; CHECK-NEXT: phi i320
}
define i160 @test14b(i320 %A, i320 %B, i1 %b1) {
BB0:
%a = trunc i320 %A to i160
%b = trunc i320 %B to i160
br label %Loop
Loop:
%C = phi i160 [ %a, %BB0 ], [ %b, %Loop ]
br i1 %b1, label %Loop, label %Exit
Exit: ; preds = %Loop
ret i160 %C
; CHECK: @test14b
; CHECK: Loop:
; CHECK-NEXT: phi i160
}
declare i64 @test15a(i64)
define i64 @test15b(i64 %A, i1 %b) {
; CHECK: @test15b
entry:
%i0 = zext i64 %A to i128
%i1 = shl i128 %i0, 64
%i = or i128 %i1, %i0
br i1 %b, label %one, label %two
; CHECK: entry:
; CHECK-NEXT: br i1 %b
one:
%x = phi i128 [%i, %entry], [%y, %two]
%x1 = lshr i128 %x, 64
%x2 = trunc i128 %x1 to i64
%c = call i64 @test15a(i64 %x2)
%c1 = zext i64 %c to i128
br label %two
; CHECK: one:
; CHECK-NEXT: phi i64
; CHECK-NEXT: %c = call i64 @test15a
two:
%y = phi i128 [%i, %entry], [%c1, %one]
%y1 = lshr i128 %y, 64
%y2 = trunc i128 %y1 to i64
%d = call i64 @test15a(i64 %y2)
%d1 = trunc i64 %d to i1
br i1 %d1, label %one, label %end
; CHECK: two:
; CHECK-NEXT: phi i64
; CHECK-NEXT: phi i64
; CHECK-NEXT: %d = call i64 @test15a
end:
%g = trunc i128 %y to i64
ret i64 %g
; CHECK: end:
; CHECK-NEXT: ret i64
}
|
