llvm-6502/test/CodeGen/SystemZ/cond-store-03.ll
Richard Sandiford aedb288d86 Add TargetLowering::prepareVolatileOrAtomicLoad
One unusual feature of the z architecture is that the result of a
previous load can be reused indefinitely for subsequent loads, even if
a cache-coherent store to that location is performed by another CPU.
A special serializing instruction must be used if you want to force
a load to be reattempted.

Since volatile loads are not supposed to be omitted in this way,
we should insert a serializing instruction before each such load.
The same goes for atomic loads.

The patch implements this at the IR->DAG boundary, in a similar way
to atomic fences.  It is a no-op for targets other than SystemZ.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196906 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-10 10:49:34 +00:00

323 lines
8.4 KiB
LLVM

; Test 32-bit conditional stores that are presented as selects.
;
; RUN: llc < %s -mtriple=s390x-linux-gnu -mcpu=z10 | FileCheck %s
declare void @foo(i32 *)
; Test the simple case, with the loaded value first.
define void @f1(i32 *%ptr, i32 %alt, i32 %limit) {
; CHECK-LABEL: f1:
; CHECK-NOT: %r2
; CHECK: jl [[LABEL:[^ ]*]]
; CHECK-NOT: %r2
; CHECK: st %r3, 0(%r2)
; CHECK: [[LABEL]]:
; CHECK: br %r14
%cond = icmp ult i32 %limit, 420
%orig = load i32 *%ptr
%res = select i1 %cond, i32 %orig, i32 %alt
store i32 %res, i32 *%ptr
ret void
}
; ...and with the loaded value second
define void @f2(i32 *%ptr, i32 %alt, i32 %limit) {
; CHECK-LABEL: f2:
; CHECK-NOT: %r2
; CHECK: jhe [[LABEL:[^ ]*]]
; CHECK-NOT: %r2
; CHECK: st %r3, 0(%r2)
; CHECK: [[LABEL]]:
; CHECK: br %r14
%cond = icmp ult i32 %limit, 420
%orig = load i32 *%ptr
%res = select i1 %cond, i32 %alt, i32 %orig
store i32 %res, i32 *%ptr
ret void
}
; Test cases where the value is explicitly sign-extended to 64 bits, with the
; loaded value first.
define void @f3(i32 *%ptr, i64 %alt, i32 %limit) {
; CHECK-LABEL: f3:
; CHECK-NOT: %r2
; CHECK: jl [[LABEL:[^ ]*]]
; CHECK-NOT: %r2
; CHECK: st %r3, 0(%r2)
; CHECK: [[LABEL]]:
; CHECK: br %r14
%cond = icmp ult i32 %limit, 420
%orig = load i32 *%ptr
%ext = sext i32 %orig to i64
%res = select i1 %cond, i64 %ext, i64 %alt
%trunc = trunc i64 %res to i32
store i32 %trunc, i32 *%ptr
ret void
}
; ...and with the loaded value second
define void @f4(i32 *%ptr, i64 %alt, i32 %limit) {
; CHECK-LABEL: f4:
; CHECK-NOT: %r2
; CHECK: jhe [[LABEL:[^ ]*]]
; CHECK-NOT: %r2
; CHECK: st %r3, 0(%r2)
; CHECK: [[LABEL]]:
; CHECK: br %r14
%cond = icmp ult i32 %limit, 420
%orig = load i32 *%ptr
%ext = sext i32 %orig to i64
%res = select i1 %cond, i64 %alt, i64 %ext
%trunc = trunc i64 %res to i32
store i32 %trunc, i32 *%ptr
ret void
}
; Test cases where the value is explicitly zero-extended to 32 bits, with the
; loaded value first.
define void @f5(i32 *%ptr, i64 %alt, i32 %limit) {
; CHECK-LABEL: f5:
; CHECK-NOT: %r2
; CHECK: jl [[LABEL:[^ ]*]]
; CHECK-NOT: %r2
; CHECK: st %r3, 0(%r2)
; CHECK: [[LABEL]]:
; CHECK: br %r14
%cond = icmp ult i32 %limit, 420
%orig = load i32 *%ptr
%ext = zext i32 %orig to i64
%res = select i1 %cond, i64 %ext, i64 %alt
%trunc = trunc i64 %res to i32
store i32 %trunc, i32 *%ptr
ret void
}
; ...and with the loaded value second
define void @f6(i32 *%ptr, i64 %alt, i32 %limit) {
; CHECK-LABEL: f6:
; CHECK-NOT: %r2
; CHECK: jhe [[LABEL:[^ ]*]]
; CHECK-NOT: %r2
; CHECK: st %r3, 0(%r2)
; CHECK: [[LABEL]]:
; CHECK: br %r14
%cond = icmp ult i32 %limit, 420
%orig = load i32 *%ptr
%ext = zext i32 %orig to i64
%res = select i1 %cond, i64 %alt, i64 %ext
%trunc = trunc i64 %res to i32
store i32 %trunc, i32 *%ptr
ret void
}
; Check the high end of the aligned ST range.
define void @f7(i32 *%base, i32 %alt, i32 %limit) {
; CHECK-LABEL: f7:
; CHECK-NOT: %r2
; CHECK: jl [[LABEL:[^ ]*]]
; CHECK-NOT: %r2
; CHECK: st %r3, 4092(%r2)
; CHECK: [[LABEL]]:
; CHECK: br %r14
%ptr = getelementptr i32 *%base, i64 1023
%cond = icmp ult i32 %limit, 420
%orig = load i32 *%ptr
%res = select i1 %cond, i32 %orig, i32 %alt
store i32 %res, i32 *%ptr
ret void
}
; Check the next word up, which should use STY instead of ST.
define void @f8(i32 *%base, i32 %alt, i32 %limit) {
; CHECK-LABEL: f8:
; CHECK-NOT: %r2
; CHECK: jl [[LABEL:[^ ]*]]
; CHECK-NOT: %r2
; CHECK: sty %r3, 4096(%r2)
; CHECK: [[LABEL]]:
; CHECK: br %r14
%ptr = getelementptr i32 *%base, i64 1024
%cond = icmp ult i32 %limit, 420
%orig = load i32 *%ptr
%res = select i1 %cond, i32 %orig, i32 %alt
store i32 %res, i32 *%ptr
ret void
}
; Check the high end of the aligned STY range.
define void @f9(i32 *%base, i32 %alt, i32 %limit) {
; CHECK-LABEL: f9:
; CHECK-NOT: %r2
; CHECK: jl [[LABEL:[^ ]*]]
; CHECK-NOT: %r2
; CHECK: sty %r3, 524284(%r2)
; CHECK: [[LABEL]]:
; CHECK: br %r14
%ptr = getelementptr i32 *%base, i64 131071
%cond = icmp ult i32 %limit, 420
%orig = load i32 *%ptr
%res = select i1 %cond, i32 %orig, i32 %alt
store i32 %res, i32 *%ptr
ret void
}
; Check the next word up, which needs separate address logic.
; Other sequences besides this one would be OK.
define void @f10(i32 *%base, i32 %alt, i32 %limit) {
; CHECK-LABEL: f10:
; CHECK-NOT: %r2
; CHECK: jl [[LABEL:[^ ]*]]
; CHECK-NOT: %r2
; CHECK: agfi %r2, 524288
; CHECK: st %r3, 0(%r2)
; CHECK: [[LABEL]]:
; CHECK: br %r14
%ptr = getelementptr i32 *%base, i64 131072
%cond = icmp ult i32 %limit, 420
%orig = load i32 *%ptr
%res = select i1 %cond, i32 %orig, i32 %alt
store i32 %res, i32 *%ptr
ret void
}
; Check the low end of the STY range.
define void @f11(i32 *%base, i32 %alt, i32 %limit) {
; CHECK-LABEL: f11:
; CHECK-NOT: %r2
; CHECK: jl [[LABEL:[^ ]*]]
; CHECK-NOT: %r2
; CHECK: sty %r3, -524288(%r2)
; CHECK: [[LABEL]]:
; CHECK: br %r14
%ptr = getelementptr i32 *%base, i64 -131072
%cond = icmp ult i32 %limit, 420
%orig = load i32 *%ptr
%res = select i1 %cond, i32 %orig, i32 %alt
store i32 %res, i32 *%ptr
ret void
}
; Check the next word down, which needs separate address logic.
; Other sequences besides this one would be OK.
define void @f12(i32 *%base, i32 %alt, i32 %limit) {
; CHECK-LABEL: f12:
; CHECK-NOT: %r2
; CHECK: jl [[LABEL:[^ ]*]]
; CHECK-NOT: %r2
; CHECK: agfi %r2, -524292
; CHECK: st %r3, 0(%r2)
; CHECK: [[LABEL]]:
; CHECK: br %r14
%ptr = getelementptr i32 *%base, i64 -131073
%cond = icmp ult i32 %limit, 420
%orig = load i32 *%ptr
%res = select i1 %cond, i32 %orig, i32 %alt
store i32 %res, i32 *%ptr
ret void
}
; Check that STY allows an index.
define void @f13(i64 %base, i64 %index, i32 %alt, i32 %limit) {
; CHECK-LABEL: f13:
; CHECK-NOT: %r2
; CHECK: jl [[LABEL:[^ ]*]]
; CHECK-NOT: %r2
; CHECK: sty %r4, 4096(%r3,%r2)
; CHECK: [[LABEL]]:
; CHECK: br %r14
%add1 = add i64 %base, %index
%add2 = add i64 %add1, 4096
%ptr = inttoptr i64 %add2 to i32 *
%cond = icmp ult i32 %limit, 420
%orig = load i32 *%ptr
%res = select i1 %cond, i32 %orig, i32 %alt
store i32 %res, i32 *%ptr
ret void
}
; Check that volatile loads are not matched.
define void @f14(i32 *%ptr, i32 %alt, i32 %limit) {
; CHECK-LABEL: f14:
; CHECK: l {{%r[0-5]}}, 0(%r2)
; CHECK: {{jl|jnl}} [[LABEL:[^ ]*]]
; CHECK: [[LABEL]]:
; CHECK: st {{%r[0-5]}}, 0(%r2)
; CHECK: br %r14
%cond = icmp ult i32 %limit, 420
%orig = load volatile i32 *%ptr
%res = select i1 %cond, i32 %orig, i32 %alt
store i32 %res, i32 *%ptr
ret void
}
; ...likewise stores. In this case we should have a conditional load into %r3.
define void @f15(i32 *%ptr, i32 %alt, i32 %limit) {
; CHECK-LABEL: f15:
; CHECK: jhe [[LABEL:[^ ]*]]
; CHECK: l %r3, 0(%r2)
; CHECK: [[LABEL]]:
; CHECK: st %r3, 0(%r2)
; CHECK: br %r14
%cond = icmp ult i32 %limit, 420
%orig = load i32 *%ptr
%res = select i1 %cond, i32 %orig, i32 %alt
store volatile i32 %res, i32 *%ptr
ret void
}
; Check that atomic loads are not matched. The transformation is OK for
; the "unordered" case tested here, but since we don't try to handle atomic
; operations at all in this context, it seems better to assert that than
; to restrict the test to a stronger ordering.
define void @f16(i32 *%ptr, i32 %alt, i32 %limit) {
; FIXME: should use a normal load instead of CS.
; CHECK-LABEL: f16:
; CHECK: l {{%r[0-5]}}, 0(%r2)
; CHECK: {{jl|jnl}} [[LABEL:[^ ]*]]
; CHECK: [[LABEL]]:
; CHECK: st {{%r[0-5]}}, 0(%r2)
; CHECK: br %r14
%cond = icmp ult i32 %limit, 420
%orig = load atomic i32 *%ptr unordered, align 4
%res = select i1 %cond, i32 %orig, i32 %alt
store i32 %res, i32 *%ptr
ret void
}
; ...likewise stores.
define void @f17(i32 *%ptr, i32 %alt, i32 %limit) {
; FIXME: should use a normal store instead of CS.
; CHECK-LABEL: f17:
; CHECK: jhe [[LABEL:[^ ]*]]
; CHECK: l %r3, 0(%r2)
; CHECK: [[LABEL]]:
; CHECK: st %r3, 0(%r2)
; CHECK: br %r14
%cond = icmp ult i32 %limit, 420
%orig = load i32 *%ptr
%res = select i1 %cond, i32 %orig, i32 %alt
store atomic i32 %res, i32 *%ptr unordered, align 4
ret void
}
; Try a frame index base.
define void @f18(i32 %alt, i32 %limit) {
; CHECK-LABEL: f18:
; CHECK: brasl %r14, foo@PLT
; CHECK-NOT: %r15
; CHECK: jl [[LABEL:[^ ]*]]
; CHECK-NOT: %r15
; CHECK: st {{%r[0-9]+}}, {{[0-9]+}}(%r15)
; CHECK: [[LABEL]]:
; CHECK: brasl %r14, foo@PLT
; CHECK: br %r14
%ptr = alloca i32
call void @foo(i32 *%ptr)
%cond = icmp ult i32 %limit, 420
%orig = load i32 *%ptr
%res = select i1 %cond, i32 %orig, i32 %alt
store i32 %res, i32 *%ptr
call void @foo(i32 *%ptr)
ret void
}