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[Test] Add a test case fo a missed oppurtunity in implicit null checking 

llvm-svn: 373813
This commit is contained in:
Philip Reames 2019-10-04 23:46:26 +00:00
parent ea835f5ce8
commit 9fe5d730c7
1 changed files with 62 additions and 6 deletions
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68
llvm/test/CodeGen/X86/implicit-null-check.ll
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@ -432,14 +432,70 @@ define i32 @imp_null_check_gep_load_with_use_dep(i32* %x, i32 %a) {
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(i32* %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 i32* %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, i32* %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(i32* %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 i32* %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, i32* %x
ret i32 %t
}
define void @imp_null_check_store(i32* %x) {
; CHECK-LABEL: imp_null_check_store:
; CHECK: ## %bb.0: ## %entry
; CHECK-NEXT: Ltmp14:
; CHECK-NEXT: movl $1, (%rdi) ## on-fault: LBB16_1
; CHECK-NEXT: movl $1, (%rdi) ## on-fault: LBB18_1
; CHECK-NEXT: ## %bb.2: ## %not_null
; CHECK-NEXT: retq
; CHECK-NEXT: LBB16_1: ## %is_null
; CHECK-NEXT: LBB18_1: ## %is_null
; CHECK-NEXT: retq
entry:
@ -459,10 +515,10 @@ define void @imp_null_check_unordered_store(i32* %x) {
; CHECK-LABEL: imp_null_check_unordered_store:
; CHECK: ## %bb.0: ## %entry
; CHECK-NEXT: Ltmp15:
; CHECK-NEXT: movl $1, (%rdi) ## on-fault: LBB17_1
; CHECK-NEXT: movl $1, (%rdi) ## on-fault: LBB19_1
; CHECK-NEXT: ## %bb.2: ## %not_null
; CHECK-NEXT: retq
; CHECK-NEXT: LBB17_1: ## %is_null
; CHECK-NEXT: LBB19_1: ## %is_null
; CHECK-NEXT: retq
entry:
@ -481,10 +537,10 @@ define i32 @imp_null_check_neg_gep_load(i32* %x) {
; CHECK-LABEL: imp_null_check_neg_gep_load:
; CHECK: ## %bb.0: ## %entry
; CHECK-NEXT: Ltmp16:
; CHECK-NEXT: movl -128(%rdi), %eax ## on-fault: LBB18_1
; CHECK-NEXT: movl -128(%rdi), %eax ## on-fault: LBB20_1
; CHECK-NEXT: ## %bb.2: ## %not_null
; CHECK-NEXT: retq
; CHECK-NEXT: LBB18_1: ## %is_null
; CHECK-NEXT: LBB20_1: ## %is_null
; CHECK-NEXT: movl $42, %eax
; CHECK-NEXT: retq