Add atomic load/store, fetch_add, fence, and is-lock-free lowering.

tests_lit/llvm2ice_tests/nacl-atomic-intrinsics.ll

+; This tests each of the supported NaCl atomic instructions for every
+; size allowed.
+
+; RUN: %llvm2ice -O2 --verbose none %s | FileCheck %s
+; RUN: %llvm2ice -Om1 --verbose none %s | FileCheck %s
+; RUN: %llvm2ice --verbose none %s | FileCheck --check-prefix=ERRORS %s
+; RUN: %llvm2iceinsts %s | %szdiff %s | FileCheck --check-prefix=DUMP %s
+; RUN: %llvm2iceinsts --pnacl %s | %szdiff %s \
+; RUN:                           | FileCheck --check-prefix=DUMP %s
+
+declare i8 @llvm.nacl.atomic.load.i8(i8*, i32)
+declare i16 @llvm.nacl.atomic.load.i16(i16*, i32)
+declare i32 @llvm.nacl.atomic.load.i32(i32*, i32)
+declare i64 @llvm.nacl.atomic.load.i64(i64*, i32)
+declare void @llvm.nacl.atomic.store.i8(i8, i8*, i32)
+declare void @llvm.nacl.atomic.store.i16(i16, i16*, i32)
+declare void @llvm.nacl.atomic.store.i32(i32, i32*, i32)
+declare void @llvm.nacl.atomic.store.i64(i64, i64*, i32)
+declare i8 @llvm.nacl.atomic.rmw.i8(i32, i8*, i8, i32)
+declare i16 @llvm.nacl.atomic.rmw.i16(i32, i16*, i16, i32)
+declare i32 @llvm.nacl.atomic.rmw.i32(i32, i32*, i32, i32)
+declare i64 @llvm.nacl.atomic.rmw.i64(i32, i64*, i64, i32)
+declare i8 @llvm.nacl.atomic.cmpxchg.i8(i8*, i8, i8, i32, i32)
+declare i16 @llvm.nacl.atomic.cmpxchg.i16(i16*, i16, i16, i32, i32)
+declare i32 @llvm.nacl.atomic.cmpxchg.i32(i32*, i32, i32, i32, i32)
+declare i64 @llvm.nacl.atomic.cmpxchg.i64(i64*, i64, i64, i32, i32)
+declare void @llvm.nacl.atomic.fence(i32)
+declare void @llvm.nacl.atomic.fence.all()
+declare i1 @llvm.nacl.atomic.is.lock.free(i32, i8*)
+
+;;; Load
+
+; x86 guarantees load/store to be atomic if naturally aligned.
+; The PNaCl IR requires all atomic accesses to be naturally aligned.
+
+define i32 @test_atomic_load_8(i32 %iptr) {
+entry:
+  %ptr = inttoptr i32 %iptr to i8*
+  ; parameter value "6" is for the sequential consistency memory order.
+  %i = call i8 @llvm.nacl.atomic.load.i8(i8* %ptr, i32 6)
+  %r = zext i8 %i to i32
+  ret i32 %r
+}
+; CHECK-LABEL: test_atomic_load_8
+; CHECK: mov {{.*}}, dword
+; CHECK: mov {{.*}}, byte
+
+define i32 @test_atomic_load_16(i32 %iptr) {
+entry:
+  %ptr = inttoptr i32 %iptr to i16*
+  %i = call i16 @llvm.nacl.atomic.load.i16(i16* %ptr, i32 6)
+  %r = zext i16 %i to i32
+  ret i32 %r
+}
+; CHECK-LABEL: test_atomic_load_16
+; CHECK: mov {{.*}}, dword
+; CHECK: mov {{.*}}, word
+
+define i32 @test_atomic_load_32(i32 %iptr) {
+entry:
+  %ptr = inttoptr i32 %iptr to i32*
+  %r = call i32 @llvm.nacl.atomic.load.i32(i32* %ptr, i32 6)
+  ret i32 %r
+}
+; CHECK-LABEL: test_atomic_load_32
+; CHECK: mov {{.*}}, dword
+; CHECK: mov {{.*}}, dword
+
+define i64 @test_atomic_load_64(i32 %iptr) {
+entry:
+  %ptr = inttoptr i32 %iptr to i64*
+  %r = call i64 @llvm.nacl.atomic.load.i64(i64* %ptr, i32 6)
+  ret i64 %r
+}
+; CHECK-LABEL: test_atomic_load_64
+; CHECK: movq x{{.*}}, qword
+; CHECK: movq qword {{.*}}, x{{.*}}
+
+define i32 @test_atomic_load_32_with_arith(i32 %iptr) {
+entry:
+  %ptr = inttoptr i32 %iptr to i32*
+  %r = call i32 @llvm.nacl.atomic.load.i32(i32* %ptr, i32 6)
+  %r2 = add i32 %r, 32
+  ret i32 %r2
+}
+; CHECK-LABEL: test_atomic_load_32_with_arith
+; CHECK: mov {{.*}}, dword
+; The next instruction may be a separate load or folded into an add.
+
+define i32 @test_atomic_load_32_ignored(i32 %iptr) {
+entry:
+  %ptr = inttoptr i32 %iptr to i32*
+  %ignored = call i32 @llvm.nacl.atomic.load.i32(i32* %ptr, i32 6)
+  ret i32 0
+}
+; CHECK-LABEL: test_atomic_load_32_ignored
+; CHECK: mov {{.*}}, dword
+; CHECK: mov {{.*}}, dword
+
+define i64 @test_atomic_load_64_ignored(i32 %iptr) {
+entry:
+  %ptr = inttoptr i32 %iptr to i64*
+  %ignored = call i64 @llvm.nacl.atomic.load.i64(i64* %ptr, i32 6)
+  ret i64 0
+}
+; CHECK-LABEL: test_atomic_load_64_ignored
+; CHECK: movq x{{.*}}, qword
+; CHECK: movq qword {{.*}}, x{{.*}}
+
+
+;;; Store
+
+define void @test_atomic_store_8(i32 %iptr, i32 %v) {
+entry:
+  %truncv = trunc i32 %v to i8
+  %ptr = inttoptr i32 %iptr to i8*
+  call void @llvm.nacl.atomic.store.i8(i8 %truncv, i8* %ptr, i32 6)
+  ret void
+}
+; CHECK-LABEL: test_atomic_store_8
+; CHECK: mov byte
+; CHECK: mfence
+
+define void @test_atomic_store_16(i32 %iptr, i32 %v) {
+entry:
+  %truncv = trunc i32 %v to i16
+  %ptr = inttoptr i32 %iptr to i16*
+  call void @llvm.nacl.atomic.store.i16(i16 %truncv, i16* %ptr, i32 6)
+  ret void
+}
+; CHECK-LABEL: test_atomic_store_16
+; CHECK: mov word
+; CHECK: mfence
+
+define void @test_atomic_store_32(i32 %iptr, i32 %v) {
+entry:
+  %ptr = inttoptr i32 %iptr to i32*
+  call void @llvm.nacl.atomic.store.i32(i32 %v, i32* %ptr, i32 6)
+  ret void
+}
+; CHECK-LABEL: test_atomic_store_32
+; CHECK: mov dword
+; CHECK: mfence
+
+define void @test_atomic_store_64(i32 %iptr, i64 %v) {
+entry:
+  %ptr = inttoptr i32 %iptr to i64*
+  call void @llvm.nacl.atomic.store.i64(i64 %v, i64* %ptr, i32 6)
+  ret void
+}
+; CHECK-LABEL: test_atomic_store_64
+; CHECK: movq x{{.*}}, qword
+; CHECK: movq qword {{.*}}, x{{.*}}
+; CHECK: mfence
+
+define void @test_atomic_store_64_const(i32 %iptr) {
+entry:
+  %ptr = inttoptr i32 %iptr to i64*
+  call void @llvm.nacl.atomic.store.i64(i64 12345678901234, i64* %ptr, i32 6)
+  ret void
+}
+; CHECK-LABEL: test_atomic_store_64_const
+; CHECK: mov {{.*}}, 1942892530
+; CHECK: mov {{.*}}, 2874
+; CHECK: movq x{{.*}}, qword
+; CHECK: movq qword {{.*}}, x{{.*}}
+; CHECK: mfence
+
+
+;;; RMW
+
+define i32 @test_atomic_rmw_add_8(i32 %iptr, i32 %v) {
+entry:
+  %trunc = trunc i32 %v to i8
+  %ptr = inttoptr i32 %iptr to i8*
+  ; "1" is an atomic add, and "6" is sequential consistency.
+  %a = call i8 @llvm.nacl.atomic.rmw.i8(i32 1, i8* %ptr, i8 %trunc, i32 6)
+  %a_ext = zext i8 %a to i32
+  ret i32 %a_ext
+}
+; CHECK-LABEL: test_atomic_rmw_add_8
+; CHECK: lock xadd byte {{.*}}, [[REG:.*]]
+; CHECK: mov {{.*}}, {{.*}}[[REG]]
+
+define i32 @test_atomic_rmw_add_16(i32 %iptr, i32 %v) {
+entry:
+  %trunc = trunc i32 %v to i16
+  %ptr = inttoptr i32 %iptr to i16*
+  %a = call i16 @llvm.nacl.atomic.rmw.i16(i32 1, i16* %ptr, i16 %trunc, i32 6)
+  %a_ext = zext i16 %a to i32
+  ret i32 %a_ext
+}
+; CHECK-LABEL: test_atomic_rmw_add_16
+; CHECK: lock xadd word {{.*}}, [[REG:.*]]
+; CHECK: mov {{.*}}, {{.*}}[[REG]]
+
+define i32 @test_atomic_rmw_add_32(i32 %iptr, i32 %v) {
+entry:
+  %ptr = inttoptr i32 %iptr to i32*
+  %a = call i32 @llvm.nacl.atomic.rmw.i32(i32 1, i32* %ptr, i32 %v, i32 6)
+  ret i32 %a
+}
+; CHECK-LABEL: test_atomic_rmw_add_32
+; CHECK: lock xadd dword {{.*}}, [[REG:.*]]
+; CHECK: mov {{.*}}, {{.*}}[[REG]]
+
+;define i64 @test_atomic_rmw_add_64(i32 %iptr, i64 %v) {
+;entry:
+;  %ptr = inttoptr i32 %iptr to i64*
+;  %a = call i64 @llvm.nacl.atomic.rmw.i64(i32 1, i64* %ptr, i64 %v, i32 6)
+;  ret i64 %a
+;}
+; CHECKLATER-LABEL: test_atomic_rmw_add_64
+; CHECKLATER: uh need a... cmpxchg8b loop.
+
+define i32 @test_atomic_rmw_add_32_ignored(i32 %iptr, i32 %v) {
+entry:
+  %ptr = inttoptr i32 %iptr to i32*
+  %ignored = call i32 @llvm.nacl.atomic.rmw.i32(i32 1, i32* %ptr, i32 %v, i32 6)
+  ret i32 %v
+}
+; CHECK-LABEL: test_atomic_rmw_add_32_ignored
+; CHECK: lock xadd dword {{.*}}, [[REG:.*]]
+
+;define i32 @test_atomic_rmw_sub_32(i32 %iptr, i32 %v) {
+;entry:
+;  %ptr = inttoptr i32 %iptr to i32*
+;  %a = call i32 @llvm.nacl.atomic.rmw.i32(i32 2, i32* %ptr, i32 %v, i32 6)
+;  ret i32 %a
+;}
+; CHECKLATER-LABEL: test_atomic_rmw_sub_32
+; CHECKLATER: neg
+; CHECKLATER: lock
+; CHECKLATER: xadd
+
+;define i32 @test_atomic_rmw_or_32(i32 %iptr, i32 %v) {
+;entry:
+;  %ptr = inttoptr i32 %iptr to i32*
+;  %a = call i32 @llvm.nacl.atomic.rmw.i32(i32 3, i32* %ptr, i32 %v, i32 6)
+;  ret i32 %a
+;}
+; CHECKLATER-LABEL: test_atomic_rmw_or_32
+; Need a cmpxchg loop.
+
+;define i32 @test_atomic_rmw_and_32(i32 %iptr, i32 %v) {
+;entry:
+;  %ptr = inttoptr i32 %iptr to i32*
+;  %a = call i32 @llvm.nacl.atomic.rmw.i32(i32 4, i32* %ptr, i32 %v, i32 6)
+;  ret i32 %a
+;}
+; CHECKLATER-LABEL: test_atomic_rmw_and_32
+; Also a cmpxchg loop.
+
+;define i32 @test_atomic_rmw_xor_32(i32 %iptr, i32 %v) {
+;entry:
+;  %ptr = inttoptr i32 %iptr to i32*
+;  %a = call i32 @llvm.nacl.atomic.rmw.i32(i32 5, i32* %ptr, i32 %v, i32 6)
+;  ret i32 %a
+;}
+; CHECKLATER-LABEL: test_atomic_rmw_xor_32
+; Also a cmpxchg loop.
+
+;define i32 @test_atomic_rmw_xchg_32(i32 %iptr, i32 %v) {
+;entry:
+;  %ptr = inttoptr i32 %iptr to i32*
+;  %a = call i32 @llvm.nacl.atomic.rmw.i32(i32 6, i32* %ptr, i32 %v, i32 6)
+;  ret i32 %a
+;}
+; CHECKLATER-LABEL: test_atomic_rmw_xchg_32
+
+;;;; Cmpxchg
+
+;define i32 @test_atomic_cmpxchg_8(i32 %iptr, i32 %expected, i32 %desired) {
+;entry:
+;  %ptr = inttoptr i32 %iptr to i8*
+;  %trunc_exp = trunc i32 %expected to i8
+;  %trunc_des = trunc i32 %desired to i8
+;  %old = call i8 @llvm.nacl.atomic.cmpxchg.i8(i8* %ptr, i8 %trunc_exp,
+;                                              i8 %trunc_des, i32 6, i32 6)
+;  %old_ext = zext i8 %old to i32
+;  ret i32 %old_ext
+;}
+; CHECKLATER-LABEL: test_atomic_cmpxchg_8
+; CHECKLATER: lock cmpxchg byte
+
+;define i32 @test_atomic_cmpxchg_16(i32 %iptr, i32 %expected, i32 %desired) {
+;entry:
+;  %ptr = inttoptr i32 %iptr to i16*
+;  %trunc_exp = trunc i32 %expected to i16
+;  %trunc_des = trunc i32 %desired to i16
+;  %old = call i16 @llvm.nacl.atomic.cmpxchg.i16(i16* %ptr, i16 %trunc_exp,
+;                                               i16 %trunc_des, i32 6, i32 6)
+;  %old_ext = zext i16 %old to i32
+;  ret i32 %old_ext
+;}
+; CHECKLATER-LABEL: test_atomic_cmpxchg_16
+; This one is a bit gross for NaCl right now.
+; https://code.google.com/p/nativeclient/issues/detail?id=2981
+; But we'll assume that NaCl will have it fixed...
+; CHECKLATER: lock cmpxchg word
+
+;define i32 @test_atomic_cmpxchg_32(i32 %iptr, i32 %expected, i32 %desired) {
+;entry:
+;  %ptr = inttoptr i32 %iptr to i32*
+;  %old = call i32 @llvm.nacl.atomic.cmpxchg.i32(i32* %ptr, i32 %expected,
+;                                               i32 %desired, i32 6, i32 6)
+;  ret i32 %old
+;}
+; CHECKLATER-LABEL: test_atomic_cmpxchg_32
+; CHECKLATER: mov eax
+; CHECKLATER: mov ecx
+; CHECKLATER: lock cmpxchg dword
+
+;define i64 @test_atomic_cmpxchg_64(i32 %iptr, i64 %expected, i64 %desired) {
+;entry:
+;  %ptr = inttoptr i32 %iptr to i64*
+;  %old = call i64 @llvm.nacl.atomic.cmpxchg.i64(i64* %ptr, i64 %expected,
+;                                               i64 %desired, i32 6, i32 6)
+;  ret i64 %old
+;}
+; CHECKLATER-LABEL: test_atomic_cmpxchg_64
+; CHECKLATER: mov eax
+; CHECKLATER: mov edx
+; CHECKLATER: mov ebx
+; CHECKLATER: mov ecx
+; CHECKLATER: lock cmpxchg8b qword
+
+;define i32 @test_atomic_cmpxchg_32_loop(i32 %iptr,
+;       i32 %expected, i32 %desired) {
+;entry:
+;  br label %loop
+;
+;loop:
+;  %cmp = phi i32 [ %expected, %entry], [%old, %loop]
+;  %ptr = inttoptr i32 %iptr to i32*
+;  %old = call i32 @llvm.nacl.atomic.cmpxchg.i32(i32* %ptr, i32 %cmp,
+;                                               i32 %desired, i32 6, i32 6)
+;  %success = icmp eq i32 %cmp, %old
+;  br i1 %success, label %done, label %loop
+;
+;done:
+;  ret i32 %old
+;}
+; CHECKLATER-LABEL: test_atomic_cmpxchg_32_loop
+
+;;;; Fence and is-lock-free.
+
+define void @test_atomic_fence() {
+entry:
+  call void @llvm.nacl.atomic.fence(i32 6)
+  ret void
+}
+; CHECK-LABEL: test_atomic_fence
+; CHECK: mfence
+
+define void @test_atomic_fence_all() {
+entry:
+  call void @llvm.nacl.atomic.fence.all()
+  ret void
+}
+; CHECK-LABEL: test_atomic_fence_all
+; CHECK: mfence
+
+define i32 @test_atomic_is_lock_free(i32 %iptr) {
+entry:
+  %ptr = inttoptr i32 %iptr to i8*
+  %i = call i1 @llvm.nacl.atomic.is.lock.free(i32 4, i8* %ptr)
+  %r = zext i1 %i to i32
+  ret i32 %r
+}
+; CHECK-LABEL: test_atomic_is_lock_free
+; CHECK: mov {{.*}}, 1
+
+define i32 @test_not_lock_free(i32 %iptr) {
+entry:
+  %ptr = inttoptr i32 %iptr to i8*
+  %i = call i1 @llvm.nacl.atomic.is.lock.free(i32 7, i8* %ptr)
+  %r = zext i1 %i to i32
+  ret i32 %r
+}
+; CHECK-LABEL: test_not_lock_free
+; CHECK: mov {{.*}}, 0
+
+; TODO(jvoung): at some point we can take advantage of the
+; fact that nacl.atomic.is.lock.free will resolve to a constant
+; (which adds DCE opportunities). Once we optimize, the test expectations
+; for this case should change.
+define i32 @test_atomic_is_lock_free_can_dce(i32 %iptr, i32 %x, i32 %y) {
+entry:
+  %ptr = inttoptr i32 %iptr to i8*
+  %i = call i1 @llvm.nacl.atomic.is.lock.free(i32 4, i8* %ptr)
+  %i_ext = zext i1 %i to i32
+  %cmp = icmp eq i32 %i_ext, 1
+  br i1 %cmp, label %lock_free, label %not_lock_free
+lock_free:
+  ret i32 %i_ext
+
+not_lock_free:
+  %z = add i32 %x, %y
+  ret i32 %z
+}
+; CHECK-LABEL: test_atomic_is_lock_free_can_dce
+; CHECK: mov {{.*}}, 1
+; CHECK: ret
+; CHECK: add
+; CHECK: ret
+
+; ERRORS-NOT: ICE translation error
+; DUMP-NOT: SZ