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|
; RUN: opt < %s -default-data-layout="e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-n8:16:32" -basicaa -gvn -S -die | FileCheck %s
; RUN: opt < %s -default-data-layout="E-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:64:64-n32" -basicaa -gvn -S -die | FileCheck %s
;; Trivial RLE test.
define i32 @test0(i32 %V, i32* %P) {
store i32 %V, i32* %P
%A = load i32* %P
ret i32 %A
; CHECK: @test0
; CHECK: ret i32 %V
}
;;===----------------------------------------------------------------------===;;
;; Tests for crashers
;;===----------------------------------------------------------------------===;;
;; PR5016
define i8 @crash0({i32, i32} %A, {i32, i32}* %P) {
store {i32, i32} %A, {i32, i32}* %P
%X = bitcast {i32, i32}* %P to i8*
%Y = load i8* %X
ret i8 %Y
}
;; No PR filed, crashed in CaptureTracker.
declare void @helper()
define void @crash1() {
tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* undef, i8* undef, i64 undef, i32 1, i1 false) nounwind
%tmp = load i8* bitcast (void ()* @helper to i8*)
%x = icmp eq i8 %tmp, 15
ret void
}
;;===----------------------------------------------------------------------===;;
;; Store -> Load and Load -> Load forwarding where src and dst are different
;; types, but where the base pointer is a must alias.
;;===----------------------------------------------------------------------===;;
;; i32 -> f32 forwarding.
define float @coerce_mustalias1(i32 %V, i32* %P) {
store i32 %V, i32* %P
%P2 = bitcast i32* %P to float*
%A = load float* %P2
ret float %A
; CHECK: @coerce_mustalias1
; CHECK-NOT: load
; CHECK: ret float
}
;; i32* -> float forwarding.
define float @coerce_mustalias2(i32* %V, i32** %P) {
store i32* %V, i32** %P
%P2 = bitcast i32** %P to float*
%A = load float* %P2
ret float %A
; CHECK: @coerce_mustalias2
; CHECK-NOT: load
; CHECK: ret float
}
;; float -> i32* forwarding.
define i32* @coerce_mustalias3(float %V, float* %P) {
store float %V, float* %P
%P2 = bitcast float* %P to i32**
%A = load i32** %P2
ret i32* %A
; CHECK: @coerce_mustalias3
; CHECK-NOT: load
; CHECK: ret i32*
}
;; i32 -> f32 load forwarding.
define float @coerce_mustalias4(i32* %P, i1 %cond) {
%A = load i32* %P
%P2 = bitcast i32* %P to float*
%B = load float* %P2
br i1 %cond, label %T, label %F
T:
ret float %B
F:
%X = bitcast i32 %A to float
ret float %X
; CHECK: @coerce_mustalias4
; CHECK: %A = load i32* %P
; CHECK-NOT: load
; CHECK: ret float
; CHECK: F:
}
;; i32 -> i8 forwarding
define i8 @coerce_mustalias5(i32 %V, i32* %P) {
store i32 %V, i32* %P
%P2 = bitcast i32* %P to i8*
%A = load i8* %P2
ret i8 %A
; CHECK: @coerce_mustalias5
; CHECK-NOT: load
; CHECK: ret i8
}
;; i64 -> float forwarding
define float @coerce_mustalias6(i64 %V, i64* %P) {
store i64 %V, i64* %P
%P2 = bitcast i64* %P to float*
%A = load float* %P2
ret float %A
; CHECK: @coerce_mustalias6
; CHECK-NOT: load
; CHECK: ret float
}
;; i64 -> i8* (32-bit) forwarding
define i8* @coerce_mustalias7(i64 %V, i64* %P) {
store i64 %V, i64* %P
%P2 = bitcast i64* %P to i8**
%A = load i8** %P2
ret i8* %A
; CHECK: @coerce_mustalias7
; CHECK-NOT: load
; CHECK: ret i8*
}
; memset -> i16 forwarding.
define signext i16 @memset_to_i16_local(i16* %A) nounwind ssp {
entry:
%conv = bitcast i16* %A to i8*
tail call void @llvm.memset.p0i8.i64(i8* %conv, i8 1, i64 200, i32 1, i1 false)
%arrayidx = getelementptr inbounds i16* %A, i64 42
%tmp2 = load i16* %arrayidx
ret i16 %tmp2
; CHECK: @memset_to_i16_local
; CHECK-NOT: load
; CHECK: ret i16 257
}
; memset -> float forwarding.
define float @memset_to_float_local(float* %A, i8 %Val) nounwind ssp {
entry:
%conv = bitcast float* %A to i8* ; <i8*> [#uses=1]
tail call void @llvm.memset.p0i8.i64(i8* %conv, i8 %Val, i64 400, i32 1, i1 false)
%arrayidx = getelementptr inbounds float* %A, i64 42 ; <float*> [#uses=1]
%tmp2 = load float* %arrayidx ; <float> [#uses=1]
ret float %tmp2
; CHECK: @memset_to_float_local
; CHECK-NOT: load
; CHECK: zext
; CHECK-NEXT: shl
; CHECK-NEXT: or
; CHECK-NEXT: shl
; CHECK-NEXT: or
; CHECK-NEXT: bitcast
; CHECK-NEXT: ret float
}
;; non-local memset -> i16 load forwarding.
define i16 @memset_to_i16_nonlocal0(i16* %P, i1 %cond) {
%P3 = bitcast i16* %P to i8*
br i1 %cond, label %T, label %F
T:
tail call void @llvm.memset.p0i8.i64(i8* %P3, i8 1, i64 400, i32 1, i1 false)
br label %Cont
F:
tail call void @llvm.memset.p0i8.i64(i8* %P3, i8 2, i64 400, i32 1, i1 false)
br label %Cont
Cont:
%P2 = getelementptr i16* %P, i32 4
%A = load i16* %P2
ret i16 %A
; CHECK: @memset_to_i16_nonlocal0
; CHECK: Cont:
; CHECK-NEXT: %A = phi i16 [ 514, %F ], [ 257, %T ]
; CHECK-NOT: load
; CHECK: ret i16 %A
}
@GCst = constant {i32, float, i32 } { i32 42, float 14., i32 97 }
; memset -> float forwarding.
define float @memcpy_to_float_local(float* %A) nounwind ssp {
entry:
%conv = bitcast float* %A to i8* ; <i8*> [#uses=1]
tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %conv, i8* bitcast ({i32, float, i32 }* @GCst to i8*), i64 12, i32 1, i1 false)
%arrayidx = getelementptr inbounds float* %A, i64 1 ; <float*> [#uses=1]
%tmp2 = load float* %arrayidx ; <float> [#uses=1]
ret float %tmp2
; CHECK: @memcpy_to_float_local
; CHECK-NOT: load
; CHECK: ret float 1.400000e+01
}
;; non-local i32/float -> i8 load forwarding.
define i8 @coerce_mustalias_nonlocal0(i32* %P, i1 %cond) {
%P2 = bitcast i32* %P to float*
%P3 = bitcast i32* %P to i8*
br i1 %cond, label %T, label %F
T:
store i32 42, i32* %P
br label %Cont
F:
store float 1.0, float* %P2
br label %Cont
Cont:
%A = load i8* %P3
ret i8 %A
; CHECK: @coerce_mustalias_nonlocal0
; CHECK: Cont:
; CHECK: %A = phi i8 [
; CHECK-NOT: load
; CHECK: ret i8 %A
}
;; non-local i32/float -> i8 load forwarding. This also tests that the "P3"
;; bitcast equivalence can be properly phi translated.
define i8 @coerce_mustalias_nonlocal1(i32* %P, i1 %cond) {
%P2 = bitcast i32* %P to float*
br i1 %cond, label %T, label %F
T:
store i32 42, i32* %P
br label %Cont
F:
store float 1.0, float* %P2
br label %Cont
Cont:
%P3 = bitcast i32* %P to i8*
%A = load i8* %P3
ret i8 %A
;; FIXME: This is disabled because this caused a miscompile in the llvm-gcc
;; bootstrap, see r82411
;
; HECK: @coerce_mustalias_nonlocal1
; HECK: Cont:
; HECK: %A = phi i8 [
; HECK-NOT: load
; HECK: ret i8 %A
}
;; non-local i32 -> i8 partial redundancy load forwarding.
define i8 @coerce_mustalias_pre0(i32* %P, i1 %cond) {
%P3 = bitcast i32* %P to i8*
br i1 %cond, label %T, label %F
T:
store i32 42, i32* %P
br label %Cont
F:
br label %Cont
Cont:
%A = load i8* %P3
ret i8 %A
; CHECK: @coerce_mustalias_pre0
; CHECK: F:
; CHECK: load i8* %P3
; CHECK: Cont:
; CHECK: %A = phi i8 [
; CHECK-NOT: load
; CHECK: ret i8 %A
}
;;===----------------------------------------------------------------------===;;
;; Store -> Load and Load -> Load forwarding where src and dst are different
;; types, and the reload is an offset from the store pointer.
;;===----------------------------------------------------------------------===;;
;; i32 -> i8 forwarding.
;; PR4216
define i8 @coerce_offset0(i32 %V, i32* %P) {
store i32 %V, i32* %P
%P2 = bitcast i32* %P to i8*
%P3 = getelementptr i8* %P2, i32 2
%A = load i8* %P3
ret i8 %A
; CHECK: @coerce_offset0
; CHECK-NOT: load
; CHECK: ret i8
}
;; non-local i32/float -> i8 load forwarding.
define i8 @coerce_offset_nonlocal0(i32* %P, i1 %cond) {
%P2 = bitcast i32* %P to float*
%P3 = bitcast i32* %P to i8*
%P4 = getelementptr i8* %P3, i32 2
br i1 %cond, label %T, label %F
T:
store i32 57005, i32* %P
br label %Cont
F:
store float 1.0, float* %P2
br label %Cont
Cont:
%A = load i8* %P4
ret i8 %A
; CHECK: @coerce_offset_nonlocal0
; CHECK: Cont:
; CHECK: %A = phi i8 [
; CHECK-NOT: load
; CHECK: ret i8 %A
}
;; non-local i32 -> i8 partial redundancy load forwarding.
define i8 @coerce_offset_pre0(i32* %P, i1 %cond) {
%P3 = bitcast i32* %P to i8*
%P4 = getelementptr i8* %P3, i32 2
br i1 %cond, label %T, label %F
T:
store i32 42, i32* %P
br label %Cont
F:
br label %Cont
Cont:
%A = load i8* %P4
ret i8 %A
; CHECK: @coerce_offset_pre0
; CHECK: F:
; CHECK: load i8* %P4
; CHECK: Cont:
; CHECK: %A = phi i8 [
; CHECK-NOT: load
; CHECK: ret i8 %A
}
define i32 @chained_load(i32** %p) {
block1:
%A = alloca i32*
%z = load i32** %p
store i32* %z, i32** %A
br i1 true, label %block2, label %block3
block2:
%a = load i32** %p
br label %block4
block3:
%b = load i32** %p
br label %block4
block4:
%c = load i32** %p
%d = load i32* %c
ret i32 %d
; CHECK: @chained_load
; CHECK: %z = load i32** %p
; CHECK-NOT: load
; CHECK: %d = load i32* %z
; CHECK-NEXT: ret i32 %d
}
declare i1 @cond() readonly
declare i1 @cond2() readonly
define i32 @phi_trans2() {
; CHECK: @phi_trans2
entry:
%P = alloca i32, i32 400
br label %F1
F1:
%A = phi i32 [1, %entry], [2, %F]
%cond2 = call i1 @cond()
br i1 %cond2, label %T1, label %TY
T1:
%P2 = getelementptr i32* %P, i32 %A
%x = load i32* %P2
%cond = call i1 @cond2()
br i1 %cond, label %TX, label %F
F:
%P3 = getelementptr i32* %P, i32 2
store i32 17, i32* %P3
store i32 42, i32* %P2 ; Provides "P[A]".
br label %F1
TX:
; This load should not be compiled to 'ret i32 42'. An overly clever
; implementation of GVN would see that we're returning 17 if the loop
; executes once or 42 if it executes more than that, but we'd have to do
; loop restructuring to expose this, and GVN shouldn't do this sort of CFG
; transformation.
; CHECK: TX:
; CHECK: ret i32 %x
ret i32 %x
TY:
ret i32 0
}
define i32 @phi_trans3(i32* %p) {
; CHECK: @phi_trans3
block1:
br i1 true, label %block2, label %block3
block2:
store i32 87, i32* %p
br label %block4
block3:
%p2 = getelementptr i32* %p, i32 43
store i32 97, i32* %p2
br label %block4
block4:
%A = phi i32 [-1, %block2], [42, %block3]
br i1 true, label %block5, label %exit
; CHECK: block4:
; CHECK-NEXT: %D = phi i32 [ 87, %block2 ], [ 97, %block3 ]
; CHECK-NOT: load
block5:
%B = add i32 %A, 1
br i1 true, label %block6, label %exit
block6:
%C = getelementptr i32* %p, i32 %B
br i1 true, label %block7, label %exit
block7:
%D = load i32* %C
ret i32 %D
; CHECK: block7:
; CHECK-NEXT: ret i32 %D
exit:
ret i32 -1
}
define i8 @phi_trans4(i8* %p) {
; CHECK: @phi_trans4
entry:
%X3 = getelementptr i8* %p, i32 192
store i8 192, i8* %X3
%X = getelementptr i8* %p, i32 4
%Y = load i8* %X
br label %loop
loop:
%i = phi i32 [4, %entry], [192, %loop]
%X2 = getelementptr i8* %p, i32 %i
%Y2 = load i8* %X2
; CHECK: loop:
; CHECK-NEXT: %Y2 = phi i8 [ %Y, %entry ], [ 0, %loop ]
; CHECK-NOT: load i8
%cond = call i1 @cond2()
%Z = bitcast i8 *%X3 to i32*
store i32 0, i32* %Z
br i1 %cond, label %loop, label %out
out:
%R = add i8 %Y, %Y2
ret i8 %R
}
define i8 @phi_trans5(i8* %p) {
; CHECK: @phi_trans5
entry:
%X4 = getelementptr i8* %p, i32 2
store i8 19, i8* %X4
%X = getelementptr i8* %p, i32 4
%Y = load i8* %X
br label %loop
loop:
%i = phi i32 [4, %entry], [3, %cont]
%X2 = getelementptr i8* %p, i32 %i
%Y2 = load i8* %X2 ; Ensure this load is not being incorrectly replaced.
%cond = call i1 @cond2()
br i1 %cond, label %cont, label %out
cont:
%Z = getelementptr i8* %X2, i32 -1
%Z2 = bitcast i8 *%Z to i32*
store i32 50462976, i32* %Z2 ;; (1 << 8) | (2 << 16) | (3 << 24)
; CHECK: store i32
; CHECK-NEXT: getelementptr i8* %p, i32 3
; CHECK-NEXT: load i8*
br label %loop
out:
%R = add i8 %Y, %Y2
ret i8 %R
}
; PR6642
define i32 @memset_to_load() nounwind readnone {
entry:
%x = alloca [256 x i32], align 4 ; <[256 x i32]*> [#uses=2]
%tmp = bitcast [256 x i32]* %x to i8* ; <i8*> [#uses=1]
call void @llvm.memset.p0i8.i64(i8* %tmp, i8 0, i64 1024, i32 4, i1 false)
%arraydecay = getelementptr inbounds [256 x i32]* %x, i32 0, i32 0 ; <i32*>
%tmp1 = load i32* %arraydecay ; <i32> [#uses=1]
ret i32 %tmp1
; CHECK: @memset_to_load
; CHECK: ret i32 0
}
;;===----------------------------------------------------------------------===;;
;; Load -> Load forwarding in partial alias case.
;;===----------------------------------------------------------------------===;;
define i32 @load_load_partial_alias(i8* %P) nounwind ssp {
entry:
%0 = bitcast i8* %P to i32*
%tmp2 = load i32* %0
%add.ptr = getelementptr inbounds i8* %P, i64 1
%tmp5 = load i8* %add.ptr
%conv = zext i8 %tmp5 to i32
%add = add nsw i32 %tmp2, %conv
ret i32 %add
; TEMPORARILYDISABLED: @load_load_partial_alias
; TEMPORARILYDISABLED: load i32*
; TEMPORARILYDISABLED-NOT: load
; TEMPORARILYDISABLED: lshr i32 {{.*}}, 8
; TEMPORARILYDISABLED-NOT: load
; TEMPORARILYDISABLED: trunc i32 {{.*}} to i8
; TEMPORARILYDISABLED-NOT: load
; TEMPORARILYDISABLED: ret i32
}
; Cross block partial alias case.
define i32 @load_load_partial_alias_cross_block(i8* %P) nounwind ssp {
entry:
%xx = bitcast i8* %P to i32*
%x1 = load i32* %xx, align 4
%cmp = icmp eq i32 %x1, 127
br i1 %cmp, label %land.lhs.true, label %if.end
land.lhs.true: ; preds = %entry
%arrayidx4 = getelementptr inbounds i8* %P, i64 1
%tmp5 = load i8* %arrayidx4, align 1
%conv6 = zext i8 %tmp5 to i32
ret i32 %conv6
if.end:
ret i32 52
; TEMPORARILY_DISABLED: @load_load_partial_alias_cross_block
; TEMPORARILY_DISABLED: land.lhs.true:
; TEMPORARILY_DISABLED-NOT: load i8
; TEMPORARILY_DISABLED: ret i32 %conv6
}
;;===----------------------------------------------------------------------===;;
;; Load Widening
;;===----------------------------------------------------------------------===;;
%widening1 = type { i32, i8, i8, i8, i8 }
@f = global %widening1 zeroinitializer, align 4
define i32 @test_widening1(i8* %P) nounwind ssp noredzone {
entry:
%tmp = load i8* getelementptr inbounds (%widening1* @f, i64 0, i32 1), align 4
%conv = zext i8 %tmp to i32
%tmp1 = load i8* getelementptr inbounds (%widening1* @f, i64 0, i32 2), align 1
%conv2 = zext i8 %tmp1 to i32
%add = add nsw i32 %conv, %conv2
ret i32 %add
; CHECK: @test_widening1
; CHECK-NOT: load
; CHECK: load i16*
; CHECK-NOT: load
; CHECK: ret i32
}
define i32 @test_widening2() nounwind ssp noredzone {
entry:
%tmp = load i8* getelementptr inbounds (%widening1* @f, i64 0, i32 1), align 4
%conv = zext i8 %tmp to i32
%tmp1 = load i8* getelementptr inbounds (%widening1* @f, i64 0, i32 2), align 1
%conv2 = zext i8 %tmp1 to i32
%add = add nsw i32 %conv, %conv2
%tmp2 = load i8* getelementptr inbounds (%widening1* @f, i64 0, i32 3), align 2
%conv3 = zext i8 %tmp2 to i32
%add2 = add nsw i32 %add, %conv3
%tmp3 = load i8* getelementptr inbounds (%widening1* @f, i64 0, i32 4), align 1
%conv4 = zext i8 %tmp3 to i32
%add3 = add nsw i32 %add2, %conv3
ret i32 %add3
; CHECK: @test_widening2
; CHECK-NOT: load
; CHECK: load i32*
; CHECK-NOT: load
; CHECK: ret i32
}
declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i32, i1) nounwind
declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture, i64, i32, i1) nounwind
;;===----------------------------------------------------------------------===;;
;; Load -> Store dependency which isn't interfered with by a call that happens
;; before the pointer was captured.
;;===----------------------------------------------------------------------===;;
%class.X = type { [8 x i8] }
@_ZTV1X = weak_odr constant [5 x i8*] zeroinitializer
@_ZTV1Y = weak_odr constant [5 x i8*] zeroinitializer
declare void @use()
declare void @use3(i8***, i8**)
; PR8908
define void @test_escape1() nounwind {
%x = alloca i8**, align 8
store i8** getelementptr inbounds ([5 x i8*]* @_ZTV1X, i64 0, i64 2), i8*** %x, align 8
call void @use() nounwind
%DEAD = load i8*** %x, align 8
call void @use3(i8*** %x, i8** %DEAD) nounwind
ret void
; CHECK: test_escape1
; CHECK-NOT: DEAD
; CHECK: ret
}
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