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|
# RUN: llc -run-pass implicit-null-checks -mtriple=x86_64-apple-macosx -o - %s | FileCheck %s
--- |
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx"
;; Positive test
define i32 @imp_null_check_with_bitwise_op_0(i32* %x, i32 %val) {
entry:
br i1 undef, label %is_null, label %not_null, !make.implicit !0
is_null:
ret i32 42
not_null:
br i1 undef, label %ret_100, label %ret_200
ret_100:
ret i32 100
ret_200:
ret i32 200
}
;; Negative test. The regalloc is such that we cannot hoist the
;; instruction materializing 2200000 into %eax
define i32 @imp_null_check_with_bitwise_op_1(i32* %x, i32 %val, i32* %ptr) {
entry:
br i1 undef, label %is_null, label %not_null, !make.implicit !0
is_null:
ret i32 undef
not_null:
br i1 undef, label %ret_100, label %ret_200
ret_100:
ret i32 100
ret_200:
ret i32 200
}
;; Negative test: IR is identical to
;; @imp_null_check_with_bitwise_op_0 but MIR differs.
define i32 @imp_null_check_with_bitwise_op_2(i32* %x, i32 %val) {
entry:
br i1 undef, label %is_null, label %not_null, !make.implicit !0
is_null:
ret i32 42
not_null:
br i1 undef, label %ret_100, label %ret_200
ret_100:
ret i32 100
ret_200:
ret i32 200
}
;; Negative test: IR is identical to
;; @imp_null_check_with_bitwise_op_0 but MIR differs.
define i32 @imp_null_check_with_bitwise_op_3(i32* %x, i32 %val) {
entry:
br i1 undef, label %is_null, label %not_null, !make.implicit !0
is_null:
ret i32 42
not_null:
br i1 undef, label %ret_100, label %ret_200
ret_100:
ret i32 100
ret_200:
ret i32 200
}
!0 = !{}
...
---
name: imp_null_check_with_bitwise_op_0
# CHECK-LABEL: name: imp_null_check_with_bitwise_op_0
alignment: 4
tracksRegLiveness: true
liveins:
- { reg: '%rdi' }
- { reg: '%esi' }
# CHECK: bb.0.entry:
# CHECK: %eax = MOV32ri 2200000
# CHECK-NEXT: %eax = FAULTING_LOAD_OP %bb.3.is_null, {{[0-9]+}}, killed %eax, killed %rdi, 1, _, 0, _, implicit-def dead %eflags :: (load 4 from %ir.x)
# CHECK-NEXT: JMP_1 %bb.1.not_null
body: |
bb.0.entry:
successors: %bb.3.is_null, %bb.1.not_null
liveins: %esi, %rdi
TEST64rr %rdi, %rdi, implicit-def %eflags
JE_1 %bb.3.is_null, implicit %eflags
bb.1.not_null:
successors: %bb.4.ret_100, %bb.2.ret_200
liveins: %esi, %rdi
%eax = MOV32ri 2200000
%eax = AND32rm killed %eax, killed %rdi, 1, _, 0, _, implicit-def dead %eflags :: (load 4 from %ir.x)
CMP32rr killed %eax, killed %esi, implicit-def %eflags
JE_1 %bb.4.ret_100, implicit %eflags
bb.2.ret_200:
%eax = MOV32ri 200
RET 0, %eax
bb.3.is_null:
%eax = MOV32ri 42
RET 0, %eax
bb.4.ret_100:
%eax = MOV32ri 100
RET 0, %eax
...
---
name: imp_null_check_with_bitwise_op_1
alignment: 4
tracksRegLiveness: true
liveins:
- { reg: '%rdi' }
- { reg: '%esi' }
- { reg: '%rdx' }
# CHECK: bb.0.entry:
# CHECK: %eax = MOV32rm killed %rdx, 1, _, 0, _ :: (volatile load 4 from %ir.ptr)
# CHECK-NEXT: TEST64rr %rdi, %rdi, implicit-def %eflags
# CHECK-NEXT: JE_1 %bb.3.is_null, implicit %eflags
body: |
bb.0.entry:
successors: %bb.3.is_null, %bb.1.not_null
liveins: %esi, %rdi, %rdx
%eax = MOV32rm killed %rdx, 1, _, 0, _ :: (volatile load 4 from %ir.ptr)
TEST64rr %rdi, %rdi, implicit-def %eflags
JE_1 %bb.3.is_null, implicit %eflags
bb.1.not_null:
successors: %bb.4.ret_100, %bb.2.ret_200
liveins: %esi, %rdi
%eax = MOV32ri 2200000
%eax = AND32rm killed %eax, killed %rdi, 1, _, 0, _, implicit-def dead %eflags :: (load 4 from %ir.x)
CMP32rr killed %eax, killed %esi, implicit-def %eflags
JE_1 %bb.4.ret_100, implicit %eflags
bb.2.ret_200:
successors: %bb.3.is_null
%eax = MOV32ri 200
bb.3.is_null:
liveins: %eax, %ah, %al, %ax, %bh, %bl, %bp, %bpl, %bx, %eax, %ebp, %ebx, %rax, %rbp, %rbx, %r12, %r13, %r14, %r15, %r12b, %r13b, %r14b, %r15b, %r12d, %r13d, %r14d, %r15d, %r12w, %r13w, %r14w, %r15w
RET 0, %eax
bb.4.ret_100:
%eax = MOV32ri 100
RET 0, %eax
...
---
name: imp_null_check_with_bitwise_op_2
# CHECK-LABEL: name: imp_null_check_with_bitwise_op_2
alignment: 4
tracksRegLiveness: true
liveins:
- { reg: '%rdi' }
- { reg: '%esi' }
# CHECK: bb.0.entry:
# CHECK: TEST64rr %rdi, %rdi, implicit-def %eflags
# CHECK-NEXT: JE_1 %bb.3.is_null, implicit %eflags
body: |
bb.0.entry:
successors: %bb.3.is_null, %bb.1.not_null
liveins: %esi, %rdi
TEST64rr %rdi, %rdi, implicit-def %eflags
JE_1 %bb.3.is_null, implicit %eflags
bb.1.not_null:
successors: %bb.4.ret_100, %bb.2.ret_200
liveins: %esi, %rdi
%eax = MOV32ri 2200000
%eax = ADD32ri killed %eax, 100, implicit-def dead %eflags
%eax = AND32rm killed %eax, killed %rdi, 1, _, 0, _, implicit-def dead %eflags :: (load 4 from %ir.x)
CMP32rr killed %eax, killed %esi, implicit-def %eflags
JE_1 %bb.4.ret_100, implicit %eflags
bb.2.ret_200:
%eax = MOV32ri 200
RET 0, %eax
bb.3.is_null:
%eax = MOV32ri 42
RET 0, %eax
bb.4.ret_100:
%eax = MOV32ri 100
RET 0, %eax
...
---
name: imp_null_check_with_bitwise_op_3
# CHECK-LABEL: name: imp_null_check_with_bitwise_op_3
alignment: 4
tracksRegLiveness: true
liveins:
- { reg: '%rdi' }
- { reg: '%rsi' }
# CHECK: bb.0.entry:
# CHECK: TEST64rr %rdi, %rdi, implicit-def %eflags
# CHECK-NEXT: JE_1 %bb.3.is_null, implicit %eflags
body: |
bb.0.entry:
successors: %bb.3.is_null, %bb.1.not_null
liveins: %rsi, %rdi
TEST64rr %rdi, %rdi, implicit-def %eflags
JE_1 %bb.3.is_null, implicit %eflags
bb.1.not_null:
successors: %bb.4.ret_100, %bb.2.ret_200
liveins: %rsi, %rdi
%rdi = MOV64ri 5000
%rdi = AND64rm killed %rdi, killed %rdi, 1, _, 0, _, implicit-def dead %eflags :: (load 4 from %ir.x)
CMP64rr killed %rdi, killed %rsi, implicit-def %eflags
JE_1 %bb.4.ret_100, implicit %eflags
bb.2.ret_200:
%eax = MOV32ri 200
RET 0, %eax
bb.3.is_null:
%eax = MOV32ri 42
RET 0, %eax
bb.4.ret_100:
%eax = MOV32ri 100
RET 0, %eax
...
|