649 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			LLVM
		
	
	
	
			
		
		
	
	
			649 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			LLVM
		
	
	
	
; RUN: llc -verify-machineinstrs -O3 -mtriple=x86_64-apple-macosx -enable-implicit-null-checks < %s | FileCheck %s
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define i32 @imp_null_check_load(ptr %x) {
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; CHECK-LABEL: imp_null_check_load:
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; CHECK:       ## %bb.0: ## %entry
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; CHECK-NEXT:  Ltmp0:
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; CHECK-NEXT:    movl (%rdi), %eax ## on-fault: LBB0_1
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; CHECK-NEXT:  ## %bb.2: ## %not_null
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; CHECK-NEXT:    retq
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; CHECK-NEXT:  LBB0_1: ## %is_null
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; CHECK-NEXT:    movl $42, %eax
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; CHECK-NEXT:    retq
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 entry:
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  %c = icmp eq ptr %x, null
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  br i1 %c, label %is_null, label %not_null, !make.implicit !0
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 is_null:
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  ret i32 42
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 not_null:
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  %t = load i32, ptr %x
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  ret i32 %t
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}
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; TODO: can make implicit
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define i32 @imp_null_check_unordered_load(ptr %x) {
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; CHECK-LABEL: imp_null_check_unordered_load:
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; CHECK:       ## %bb.0: ## %entry
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; CHECK-NEXT:  Ltmp1:
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; CHECK-NEXT:    movl (%rdi), %eax ## on-fault: LBB1_1
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; CHECK-NEXT:  ## %bb.2: ## %not_null
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; CHECK-NEXT:    retq
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; CHECK-NEXT:  LBB1_1: ## %is_null
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; CHECK-NEXT:    movl $42, %eax
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; CHECK-NEXT:    retq
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 entry:
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  %c = icmp eq ptr %x, null
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  br i1 %c, label %is_null, label %not_null, !make.implicit !0
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 is_null:
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  ret i32 42
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 not_null:
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  %t = load atomic i32, ptr %x unordered, align 4
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  ret i32 %t
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}
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; TODO: Can be converted into implicit check.
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;; Probably could be implicit, but we're conservative for now
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define i32 @imp_null_check_seq_cst_load(ptr %x) {
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; CHECK-LABEL: imp_null_check_seq_cst_load:
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; CHECK:       ## %bb.0: ## %entry
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; CHECK-NEXT:    testq %rdi, %rdi
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; CHECK-NEXT:    je LBB2_1
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; CHECK-NEXT:  ## %bb.2: ## %not_null
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; CHECK-NEXT:    movl (%rdi), %eax
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; CHECK-NEXT:    retq
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; CHECK-NEXT:  LBB2_1: ## %is_null
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; CHECK-NEXT:    movl $42, %eax
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; CHECK-NEXT:    retq
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 entry:
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  %c = icmp eq ptr %x, null
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  br i1 %c, label %is_null, label %not_null, !make.implicit !0
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 is_null:
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  ret i32 42
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 not_null:
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  %t = load atomic i32, ptr %x seq_cst, align 4
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  ret i32 %t
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}
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;; Might be memory mapped IO, so can't rely on fault behavior
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define i32 @imp_null_check_volatile_load(ptr %x) {
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; CHECK-LABEL: imp_null_check_volatile_load:
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; CHECK:       ## %bb.0: ## %entry
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; CHECK-NEXT:    testq %rdi, %rdi
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; CHECK-NEXT:    je LBB3_1
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; CHECK-NEXT:  ## %bb.2: ## %not_null
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; CHECK-NEXT:    movl (%rdi), %eax
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; CHECK-NEXT:    retq
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; CHECK-NEXT:  LBB3_1: ## %is_null
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; CHECK-NEXT:    movl $42, %eax
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; CHECK-NEXT:    retq
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 entry:
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  %c = icmp eq ptr %x, null
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  br i1 %c, label %is_null, label %not_null, !make.implicit !0
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 is_null:
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  ret i32 42
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 not_null:
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  %t = load volatile i32, ptr %x, align 4
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  ret i32 %t
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}
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define i8 @imp_null_check_load_i8(ptr %x) {
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; CHECK-LABEL: imp_null_check_load_i8:
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; CHECK:       ## %bb.0: ## %entry
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; CHECK-NEXT:  Ltmp2:
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; CHECK-NEXT:    movb (%rdi), %al ## on-fault: LBB4_1
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; CHECK-NEXT:  ## %bb.2: ## %not_null
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; CHECK-NEXT:    retq
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; CHECK-NEXT:  LBB4_1: ## %is_null
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; CHECK-NEXT:    movb $42, %al
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; CHECK-NEXT:    retq
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 entry:
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  %c = icmp eq ptr %x, null
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  br i1 %c, label %is_null, label %not_null, !make.implicit !0
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 is_null:
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  ret i8 42
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 not_null:
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  %t = load i8, ptr %x
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  ret i8 %t
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}
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define i256 @imp_null_check_load_i256(ptr %x) {
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; CHECK-LABEL: imp_null_check_load_i256:
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; CHECK:       ## %bb.0: ## %entry
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; CHECK-NEXT:    movq %rdi, %rax
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; CHECK-NEXT:  Ltmp3:
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; CHECK-NEXT:    movq (%rsi), %rcx ## on-fault: LBB5_1
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; CHECK-NEXT:  ## %bb.2: ## %not_null
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; CHECK-NEXT:    movq 8(%rsi), %rdx
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; CHECK-NEXT:    movq 16(%rsi), %rdi
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; CHECK-NEXT:    movq 24(%rsi), %rsi
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; CHECK-NEXT:    movq %rsi, 24(%rax)
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; CHECK-NEXT:    movq %rdi, 16(%rax)
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; CHECK-NEXT:    movq %rdx, 8(%rax)
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; CHECK-NEXT:    movq %rcx, (%rax)
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; CHECK-NEXT:    retq
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; CHECK-NEXT:  LBB5_1: ## %is_null
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; CHECK-NEXT:    movq $0, 24(%rax)
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; CHECK-NEXT:    movq $0, 16(%rax)
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; CHECK-NEXT:    movq $0, 8(%rax)
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; CHECK-NEXT:    movq $42, (%rax)
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; CHECK-NEXT:    retq
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 entry:
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  %c = icmp eq ptr %x, null
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  br i1 %c, label %is_null, label %not_null, !make.implicit !0
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 is_null:
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  ret i256 42
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 not_null:
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  %t = load i256, ptr %x
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  ret i256 %t
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}
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define i32 @imp_null_check_gep_load(ptr %x) {
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; CHECK-LABEL: imp_null_check_gep_load:
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; CHECK:       ## %bb.0: ## %entry
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; CHECK-NEXT:  Ltmp4:
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; CHECK-NEXT:    movl 128(%rdi), %eax ## on-fault: LBB6_1
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; CHECK-NEXT:  ## %bb.2: ## %not_null
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; CHECK-NEXT:    retq
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; CHECK-NEXT:  LBB6_1: ## %is_null
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; CHECK-NEXT:    movl $42, %eax
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; CHECK-NEXT:    retq
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 entry:
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  %c = icmp eq ptr %x, null
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  br i1 %c, label %is_null, label %not_null, !make.implicit !0
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 is_null:
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  ret i32 42
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 not_null:
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  %x.gep = getelementptr i32, ptr %x, i32 32
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  %t = load i32, ptr %x.gep
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  ret i32 %t
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}
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define i32 @imp_null_check_add_result(ptr %x, i32 %p) {
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; CHECK-LABEL: imp_null_check_add_result:
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; CHECK:       ## %bb.0: ## %entry
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; CHECK-NEXT:  Ltmp5:
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; CHECK-NEXT:    addl (%rdi), %esi ## on-fault: LBB7_1
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; CHECK-NEXT:  ## %bb.2: ## %not_null
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; CHECK-NEXT:    movl %esi, %eax
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; CHECK-NEXT:    retq
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; CHECK-NEXT:  LBB7_1: ## %is_null
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; CHECK-NEXT:    movl $42, %eax
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; CHECK-NEXT:    retq
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 entry:
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  %c = icmp eq ptr %x, null
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  br i1 %c, label %is_null, label %not_null, !make.implicit !0
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 is_null:
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  ret i32 42
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 not_null:
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  %t = load i32, ptr %x
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  %p1 = add i32 %t, %p
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  ret i32 %p1
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}
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define i32 @imp_null_check_sub_result(ptr %x, i32 %p) {
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; CHECK-LABEL: imp_null_check_sub_result:
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; CHECK:       ## %bb.0: ## %entry
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; CHECK-NEXT:  Ltmp6:
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; CHECK-NEXT:    movl (%rdi), %eax ## on-fault: LBB8_1
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; CHECK-NEXT:  ## %bb.2: ## %not_null
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; CHECK-NEXT:    subl %esi, %eax
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; CHECK-NEXT:    retq
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; CHECK-NEXT:  LBB8_1: ## %is_null
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; CHECK-NEXT:    movl $42, %eax
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; CHECK-NEXT:    retq
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 entry:
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  %c = icmp eq ptr %x, null
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  br i1 %c, label %is_null, label %not_null, !make.implicit !0
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 is_null:
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  ret i32 42
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 not_null:
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  %t = load i32, ptr %x
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  %p1 = sub i32 %t, %p
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  ret i32 %p1
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}
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define i32 @imp_null_check_mul_result(ptr %x, i32 %p) {
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; CHECK-LABEL: imp_null_check_mul_result:
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; CHECK:       ## %bb.0: ## %entry
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; CHECK-NEXT:  Ltmp7:
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; CHECK-NEXT:    imull (%rdi), %esi ## on-fault: LBB9_1
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; CHECK-NEXT:  ## %bb.2: ## %not_null
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; CHECK-NEXT:    movl %esi, %eax
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; CHECK-NEXT:    retq
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; CHECK-NEXT:  LBB9_1: ## %is_null
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; CHECK-NEXT:    movl $42, %eax
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; CHECK-NEXT:    retq
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 entry:
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  %c = icmp eq ptr %x, null
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  br i1 %c, label %is_null, label %not_null, !make.implicit !0
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 is_null:
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  ret i32 42
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 not_null:
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  %t = load i32, ptr %x
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  %p1 = mul i32 %t, %p
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  ret i32 %p1
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}
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define i32 @imp_null_check_udiv_result(ptr %x, i32 %p) {
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; CHECK-LABEL: imp_null_check_udiv_result:
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; CHECK:       ## %bb.0: ## %entry
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; CHECK-NEXT:  Ltmp8:
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; CHECK-NEXT:    movl (%rdi), %eax ## on-fault: LBB10_1
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; CHECK-NEXT:  ## %bb.2: ## %not_null
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; CHECK-NEXT:    xorl %edx, %edx
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; CHECK-NEXT:    divl %esi
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; CHECK-NEXT:    retq
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; CHECK-NEXT:  LBB10_1: ## %is_null
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; CHECK-NEXT:    movl $42, %eax
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; CHECK-NEXT:    retq
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 entry:
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  %c = icmp eq ptr %x, null
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  br i1 %c, label %is_null, label %not_null, !make.implicit !0
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 is_null:
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  ret i32 42
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 not_null:
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  %t = load i32, ptr %x
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  %p1 = udiv i32 %t, %p
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  ret i32 %p1
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}
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define i32 @imp_null_check_shl_result(ptr %x, i32 %p) {
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; CHECK-LABEL: imp_null_check_shl_result:
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; CHECK:       ## %bb.0: ## %entry
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; CHECK-NEXT:  Ltmp9:
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; CHECK-NEXT:    movl (%rdi), %eax ## on-fault: LBB11_1
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; CHECK-NEXT:  ## %bb.2: ## %not_null
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; CHECK-NEXT:    movl %esi, %ecx
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; CHECK-NEXT:    shll %cl, %eax
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; CHECK-NEXT:    retq
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; CHECK-NEXT:  LBB11_1: ## %is_null
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; CHECK-NEXT:    movl $42, %eax
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; CHECK-NEXT:    retq
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 entry:
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  %c = icmp eq ptr %x, null
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  br i1 %c, label %is_null, label %not_null, !make.implicit !0
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 is_null:
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  ret i32 42
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 not_null:
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  %t = load i32, ptr %x
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  %p1 = shl i32 %t, %p
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  ret i32 %p1
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}
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define i32 @imp_null_check_lshr_result(ptr %x, i32 %p) {
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; CHECK-LABEL: imp_null_check_lshr_result:
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; CHECK:       ## %bb.0: ## %entry
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; CHECK-NEXT:  Ltmp10:
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; CHECK-NEXT:    movl (%rdi), %eax ## on-fault: LBB12_1
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; CHECK-NEXT:  ## %bb.2: ## %not_null
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; CHECK-NEXT:    movl %esi, %ecx
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; CHECK-NEXT:    shrl %cl, %eax
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; CHECK-NEXT:    retq
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; CHECK-NEXT:  LBB12_1: ## %is_null
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; CHECK-NEXT:    movl $42, %eax
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; CHECK-NEXT:    retq
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 entry:
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  %c = icmp eq ptr %x, null
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  br i1 %c, label %is_null, label %not_null, !make.implicit !0
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 is_null:
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  ret i32 42
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 not_null:
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  %t = load i32, ptr %x
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  %p1 = lshr i32 %t, %p
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  ret i32 %p1
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}
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define i32 @imp_null_check_hoist_over_unrelated_load(ptr %x, ptr %y, ptr %z) {
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; CHECK-LABEL: imp_null_check_hoist_over_unrelated_load:
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; CHECK:       ## %bb.0: ## %entry
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; CHECK-NEXT:  Ltmp11:
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; CHECK-NEXT:    movl (%rdi), %eax ## on-fault: LBB13_1
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; CHECK-NEXT:  ## %bb.2: ## %not_null
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; CHECK-NEXT:    movl (%rsi), %ecx
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; CHECK-NEXT:    movl %ecx, (%rdx)
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; CHECK-NEXT:    retq
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; CHECK-NEXT:  LBB13_1: ## %is_null
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; CHECK-NEXT:    movl $42, %eax
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; CHECK-NEXT:    retq
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 entry:
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  %c = icmp eq ptr %x, null
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  br i1 %c, label %is_null, label %not_null, !make.implicit !0
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 is_null:
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  ret i32 42
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 not_null:
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  %t0 = load i32, ptr %y
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  %t1 = load i32, ptr %x
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  store i32 %t0, ptr %z
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  ret i32 %t1
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}
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define i32 @imp_null_check_via_mem_comparision(ptr %x, i32 %val) {
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; CHECK-LABEL: imp_null_check_via_mem_comparision:
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; CHECK:       ## %bb.0: ## %entry
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; CHECK-NEXT:  Ltmp12:
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; CHECK-NEXT:    cmpl %esi, 4(%rdi) ## on-fault: LBB14_3
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; CHECK-NEXT:  ## %bb.1: ## %not_null
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; CHECK-NEXT:    jge LBB14_2
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; CHECK-NEXT:  ## %bb.4: ## %ret_100
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; CHECK-NEXT:    movl $100, %eax
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; CHECK-NEXT:    retq
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; CHECK-NEXT:  LBB14_3: ## %is_null
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; CHECK-NEXT:    movl $42, %eax
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; CHECK-NEXT:    retq
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; CHECK-NEXT:  LBB14_2: ## %ret_200
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; CHECK-NEXT:    movl $200, %eax
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; CHECK-NEXT:    retq
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 entry:
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  %c = icmp eq ptr %x, null
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  br i1 %c, label %is_null, label %not_null, !make.implicit !0
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 is_null:
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  ret i32 42
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 not_null:
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  %x.loc = getelementptr i32, ptr %x, i32 1
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  %t = load i32, ptr %x.loc
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  %m = icmp slt i32 %t, %val
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  br i1 %m, label %ret_100, label %ret_200
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 ret_100:
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  ret i32 100
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 ret_200:
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  ret i32 200
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}
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define i32 @imp_null_check_gep_load_with_use_dep(ptr %x, i32 %a) {
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; CHECK-LABEL: imp_null_check_gep_load_with_use_dep:
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; CHECK:       ## %bb.0: ## %entry
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; CHECK-NEXT:    ## kill: def $esi killed $esi def $rsi
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; CHECK-NEXT:  Ltmp13:
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; CHECK-NEXT:    movl (%rdi), %eax ## on-fault: LBB15_1
 | 
						|
; CHECK-NEXT:  ## %bb.2: ## %not_null
 | 
						|
; CHECK-NEXT:    addl %edi, %esi
 | 
						|
; CHECK-NEXT:    leal 4(%rax,%rsi), %eax
 | 
						|
; CHECK-NEXT:    retq
 | 
						|
; CHECK-NEXT:  LBB15_1: ## %is_null
 | 
						|
; CHECK-NEXT:    movl $42, %eax
 | 
						|
; CHECK-NEXT:    retq
 | 
						|
 | 
						|
 entry:
 | 
						|
  %c = icmp eq ptr %x, null
 | 
						|
  br i1 %c, label %is_null, label %not_null, !make.implicit !0
 | 
						|
 | 
						|
 is_null:
 | 
						|
  ret i32 42
 | 
						|
 | 
						|
 not_null:
 | 
						|
  %x.loc = getelementptr i32, ptr %x, i32 1
 | 
						|
  %y = ptrtoint ptr %x.loc to i32
 | 
						|
  %b = add i32 %a, %y
 | 
						|
  %t = load i32, ptr %x
 | 
						|
  %z = add i32 %t, %b
 | 
						|
  ret i32 %z
 | 
						|
}
 | 
						|
 | 
						|
;; TODO: We could handle this case as we can lift the fence into the
 | 
						|
;; previous block before the conditional without changing behavior.
 | 
						|
define i32 @imp_null_check_load_fence1(ptr %x) {
 | 
						|
; CHECK-LABEL: imp_null_check_load_fence1:
 | 
						|
; CHECK:       ## %bb.0: ## %entry
 | 
						|
; CHECK-NEXT:    testq %rdi, %rdi
 | 
						|
; CHECK-NEXT:    je LBB16_1
 | 
						|
; CHECK-NEXT:  ## %bb.2: ## %not_null
 | 
						|
; CHECK-NEXT:    ##MEMBARRIER
 | 
						|
; CHECK-NEXT:    movl (%rdi), %eax
 | 
						|
; CHECK-NEXT:    retq
 | 
						|
; CHECK-NEXT:  LBB16_1: ## %is_null
 | 
						|
; CHECK-NEXT:    movl $42, %eax
 | 
						|
; CHECK-NEXT:    retq
 | 
						|
 | 
						|
entry:
 | 
						|
  %c = icmp eq ptr %x, null
 | 
						|
  br i1 %c, label %is_null, label %not_null, !make.implicit !0
 | 
						|
 | 
						|
is_null:
 | 
						|
  ret i32 42
 | 
						|
 | 
						|
not_null:
 | 
						|
  fence acquire
 | 
						|
  %t = load i32, ptr %x
 | 
						|
  ret i32 %t
 | 
						|
}
 | 
						|
 | 
						|
;; TODO: We could handle this case as we can lift the fence into the
 | 
						|
;; previous block before the conditional without changing behavior.
 | 
						|
define i32 @imp_null_check_load_fence2(ptr %x) {
 | 
						|
; CHECK-LABEL: imp_null_check_load_fence2:
 | 
						|
; CHECK:       ## %bb.0: ## %entry
 | 
						|
; CHECK-NEXT:    testq %rdi, %rdi
 | 
						|
; CHECK-NEXT:    je LBB17_1
 | 
						|
; CHECK-NEXT:  ## %bb.2: ## %not_null
 | 
						|
; CHECK-NEXT:    mfence
 | 
						|
; CHECK-NEXT:    movl (%rdi), %eax
 | 
						|
; CHECK-NEXT:    retq
 | 
						|
; CHECK-NEXT:  LBB17_1: ## %is_null
 | 
						|
; CHECK-NEXT:    movl $42, %eax
 | 
						|
; CHECK-NEXT:    retq
 | 
						|
 | 
						|
entry:
 | 
						|
  %c = icmp eq ptr %x, null
 | 
						|
  br i1 %c, label %is_null, label %not_null, !make.implicit !0
 | 
						|
 | 
						|
is_null:
 | 
						|
  ret i32 42
 | 
						|
 | 
						|
not_null:
 | 
						|
  fence seq_cst
 | 
						|
  %t = load i32, ptr %x
 | 
						|
  ret i32 %t
 | 
						|
}
 | 
						|
 | 
						|
define void @imp_null_check_store(ptr %x) {
 | 
						|
; CHECK-LABEL: imp_null_check_store:
 | 
						|
; CHECK:       ## %bb.0: ## %entry
 | 
						|
; CHECK-NEXT:  Ltmp14:
 | 
						|
; CHECK-NEXT:    movl $1, (%rdi) ## on-fault: LBB18_1
 | 
						|
; CHECK-NEXT:  ## %bb.2: ## %not_null
 | 
						|
; CHECK-NEXT:    retq
 | 
						|
; CHECK-NEXT:  LBB18_1: ## %is_null
 | 
						|
; CHECK-NEXT:    retq
 | 
						|
 | 
						|
 entry:
 | 
						|
  %c = icmp eq ptr %x, null
 | 
						|
  br i1 %c, label %is_null, label %not_null, !make.implicit !0
 | 
						|
 | 
						|
 is_null:
 | 
						|
  ret void
 | 
						|
 | 
						|
 not_null:
 | 
						|
  store i32 1, ptr %x
 | 
						|
  ret void
 | 
						|
}
 | 
						|
 | 
						|
;; TODO: can be implicit
 | 
						|
define void @imp_null_check_unordered_store(ptr %x) {
 | 
						|
; CHECK-LABEL: imp_null_check_unordered_store:
 | 
						|
; CHECK:       ## %bb.0: ## %entry
 | 
						|
; CHECK-NEXT:  Ltmp15:
 | 
						|
; CHECK-NEXT:    movl $1, (%rdi) ## on-fault: LBB19_1
 | 
						|
; CHECK-NEXT:  ## %bb.2: ## %not_null
 | 
						|
; CHECK-NEXT:    retq
 | 
						|
; CHECK-NEXT:  LBB19_1: ## %is_null
 | 
						|
; CHECK-NEXT:    retq
 | 
						|
 | 
						|
 entry:
 | 
						|
  %c = icmp eq ptr %x, null
 | 
						|
  br i1 %c, label %is_null, label %not_null, !make.implicit !0
 | 
						|
 | 
						|
 is_null:
 | 
						|
  ret void
 | 
						|
 | 
						|
 not_null:
 | 
						|
  store atomic i32 1, ptr %x unordered, align 4
 | 
						|
  ret void
 | 
						|
}
 | 
						|
 | 
						|
define i32 @imp_null_check_neg_gep_load(ptr %x) {
 | 
						|
; CHECK-LABEL: imp_null_check_neg_gep_load:
 | 
						|
; CHECK:       ## %bb.0: ## %entry
 | 
						|
; CHECK-NEXT:  Ltmp16:
 | 
						|
; CHECK-NEXT:    movl -128(%rdi), %eax ## on-fault: LBB20_1
 | 
						|
; CHECK-NEXT:  ## %bb.2: ## %not_null
 | 
						|
; CHECK-NEXT:    retq
 | 
						|
; CHECK-NEXT:  LBB20_1: ## %is_null
 | 
						|
; CHECK-NEXT:    movl $42, %eax
 | 
						|
; CHECK-NEXT:    retq
 | 
						|
 | 
						|
 entry:
 | 
						|
  %c = icmp eq ptr %x, null
 | 
						|
  br i1 %c, label %is_null, label %not_null, !make.implicit !0
 | 
						|
 | 
						|
 is_null:
 | 
						|
  ret i32 42
 | 
						|
 | 
						|
 not_null:
 | 
						|
  %x.gep = getelementptr i32, ptr %x, i32 -32
 | 
						|
  %t = load i32, ptr %x.gep
 | 
						|
  ret i32 %t
 | 
						|
}
 | 
						|
 | 
						|
; This redefines the null check reg by doing a zero-extend and a shift on
 | 
						|
; itself.
 | 
						|
; Converted into implicit null check since both of these operations do not
 | 
						|
; change the nullness of %x (i.e. if it is null, it remains null).
 | 
						|
define i64 @imp_null_check_load_shift_addr(ptr %x) {
 | 
						|
; CHECK-LABEL: imp_null_check_load_shift_addr:
 | 
						|
; CHECK:       ## %bb.0: ## %entry
 | 
						|
; CHECK-NEXT:    shlq $6, %rdi
 | 
						|
; CHECK-NEXT:  Ltmp17:
 | 
						|
; CHECK-NEXT:    movq 8(%rdi), %rax ## on-fault: LBB21_1
 | 
						|
; CHECK-NEXT:  ## %bb.2: ## %not_null
 | 
						|
; CHECK-NEXT:    retq
 | 
						|
; CHECK-NEXT:  LBB21_1: ## %is_null
 | 
						|
; CHECK-NEXT:    movl $42, %eax
 | 
						|
; CHECK-NEXT:    retq
 | 
						|
 | 
						|
  entry:
 | 
						|
   %c = icmp eq ptr %x, null
 | 
						|
   br i1 %c, label %is_null, label %not_null, !make.implicit !0
 | 
						|
 | 
						|
  is_null:
 | 
						|
   ret i64 42
 | 
						|
 | 
						|
  not_null:
 | 
						|
   %y = ptrtoint ptr %x to i64
 | 
						|
   %shry = shl i64 %y, 6
 | 
						|
   %y.ptr = inttoptr i64 %shry to ptr
 | 
						|
   %x.loc = getelementptr i64, ptr %y.ptr, i64 1
 | 
						|
   %t = load i64, ptr %x.loc
 | 
						|
   ret i64 %t
 | 
						|
}
 | 
						|
 | 
						|
; Same as imp_null_check_load_shift_addr but shift is by 3 and this is now
 | 
						|
; converted into complex addressing.
 | 
						|
define i64 @imp_null_check_load_shift_by_3_addr(ptr %x) {
 | 
						|
; CHECK-LABEL: imp_null_check_load_shift_by_3_addr:
 | 
						|
; CHECK:       ## %bb.0: ## %entry
 | 
						|
; CHECK-NEXT:  Ltmp18:
 | 
						|
; CHECK-NEXT:    movq 8(,%rdi,8), %rax ## on-fault: LBB22_1
 | 
						|
; CHECK-NEXT:  ## %bb.2: ## %not_null
 | 
						|
; CHECK-NEXT:    retq
 | 
						|
; CHECK-NEXT:  LBB22_1: ## %is_null
 | 
						|
; CHECK-NEXT:    movl $42, %eax
 | 
						|
; CHECK-NEXT:    retq
 | 
						|
 | 
						|
  entry:
 | 
						|
   %c = icmp eq ptr %x, null
 | 
						|
   br i1 %c, label %is_null, label %not_null, !make.implicit !0
 | 
						|
 | 
						|
  is_null:
 | 
						|
   ret i64 42
 | 
						|
 | 
						|
  not_null:
 | 
						|
   %y = ptrtoint ptr %x to i64
 | 
						|
   %shry = shl i64 %y, 3
 | 
						|
   %y.ptr = inttoptr i64 %shry to ptr
 | 
						|
   %x.loc = getelementptr i64, ptr %y.ptr, i64 1
 | 
						|
   %t = load i64, ptr %x.loc
 | 
						|
   ret i64 %t
 | 
						|
}
 | 
						|
 | 
						|
define i64 @imp_null_check_load_shift_add_addr(ptr %x) {
 | 
						|
; CHECK-LABEL: imp_null_check_load_shift_add_addr:
 | 
						|
; CHECK:       ## %bb.0: ## %entry
 | 
						|
; CHECK:         movq 3526(,%rdi,8), %rax ## on-fault: LBB23_1
 | 
						|
; CHECK-NEXT:  ## %bb.2: ## %not_null
 | 
						|
; CHECK-NEXT:    retq
 | 
						|
; CHECK-NEXT:  LBB23_1: ## %is_null
 | 
						|
; CHECK-NEXT:    movl $42, %eax
 | 
						|
; CHECK-NEXT:    retq
 | 
						|
 | 
						|
  entry:
 | 
						|
   %c = icmp eq ptr %x, null
 | 
						|
   br i1 %c, label %is_null, label %not_null, !make.implicit !0
 | 
						|
 | 
						|
  is_null:
 | 
						|
   ret i64 42
 | 
						|
 | 
						|
  not_null:
 | 
						|
   %y = ptrtoint ptr %x to i64
 | 
						|
   %shry = shl i64 %y, 3
 | 
						|
   %shry.add = add i64 %shry, 3518
 | 
						|
   %y.ptr = inttoptr i64 %shry.add to ptr
 | 
						|
   %x.loc = getelementptr i64, ptr %y.ptr, i64 1
 | 
						|
   %t = load i64, ptr %x.loc
 | 
						|
   ret i64 %t
 | 
						|
}
 | 
						|
!0 = !{}
 |