llvm-project/llvm/test/CodeGen/AArch64/arm64-patchpoint.ll
Geoff Berry a5335647d5 [AArch64] Combine callee-save and local stack SP adjustment instructions.
Summary:
If a function needs to allocate both callee-save stack memory and local
stack memory, we currently decrement/increment the SP in two steps:
first for the callee-save area, and then for the local stack area.  This
changes the code to allocate them both at once at the very beginning/end
of the function.  This has two benefits:

1) there is one fewer sub/add micro-op in the prologue/epilogue

2) the stack adjustment instructions act as a scheduling barrier, so
moving them to the very beginning/end of the function increases post-RA
scheduler's ability to move instructions (that only depend on argument
registers) before any of the callee-save stores

This change can cause an increase in instructions if the original local
stack SP decrement could be folded into the first store to the stack.
This occurs when the first local stack store is to stack offset 0.  In
this case we are trading off one more sub instruction for one fewer sub
micro-op (along with benefits (2) and (3) above).

Reviewers: t.p.northover

Subscribers: aemerson, rengolin, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D18619

llvm-svn: 268746
2016-05-06 16:34:59 +00:00

86 lines
3.5 KiB
LLVM

; RUN: llc -mtriple=arm64-apple-darwin -enable-misched=0 -mcpu=cyclone < %s | FileCheck %s
; RUN: llc -mtriple=arm64-apple-darwin -enable-misched=0 -mcpu=cyclone -fast-isel -fast-isel-abort=1 < %s | FileCheck %s
; Trivial patchpoint codegen
;
define i64 @trivial_patchpoint_codegen(i64 %p1, i64 %p2, i64 %p3, i64 %p4) {
entry:
; CHECK-LABEL: trivial_patchpoint_codegen:
; CHECK: movz x16, #0xdead, lsl #32
; CHECK-NEXT: movk x16, #0xbeef, lsl #16
; CHECK-NEXT: movk x16, #0xcafe
; CHECK-NEXT: blr x16
; CHECK: movz x16, #0xdead, lsl #32
; CHECK-NEXT: movk x16, #0xbeef, lsl #16
; CHECK-NEXT: movk x16, #0xcaff
; CHECK-NEXT: blr x16
; CHECK: ret
%resolveCall2 = inttoptr i64 244837814094590 to i8*
%result = tail call i64 (i64, i32, i8*, i32, ...) @llvm.experimental.patchpoint.i64(i64 2, i32 20, i8* %resolveCall2, i32 4, i64 %p1, i64 %p2, i64 %p3, i64 %p4)
%resolveCall3 = inttoptr i64 244837814094591 to i8*
tail call void (i64, i32, i8*, i32, ...) @llvm.experimental.patchpoint.void(i64 3, i32 20, i8* %resolveCall3, i32 2, i64 %p1, i64 %result)
ret i64 %result
}
; Caller frame metadata with stackmaps. This should not be optimized
; as a leaf function.
;
; CHECK-LABEL: caller_meta_leaf
; CHECK: sub sp, sp, #48
; CHECK-NEXT: stp x29, x30, [sp, #32]
; CHECK-NEXT: add x29, sp, #32
; CHECK: Ltmp
; CHECK: add sp, sp, #48
; CHECK: ret
define void @caller_meta_leaf() {
entry:
%metadata = alloca i64, i32 3, align 8
store i64 11, i64* %metadata
store i64 12, i64* %metadata
store i64 13, i64* %metadata
call void (i64, i32, ...) @llvm.experimental.stackmap(i64 4, i32 0, i64* %metadata)
ret void
}
; Test patchpoints reusing the same TargetConstant.
; <rdar:15390785> Assertion failed: (CI.getNumArgOperands() >= NumArgs + 4)
; There is no way to verify this, since it depends on memory allocation.
; But I think it's useful to include as a working example.
define i64 @testLowerConstant(i64 %arg, i64 %tmp2, i64 %tmp10, i64* %tmp33, i64 %tmp79) {
entry:
%tmp80 = add i64 %tmp79, -16
%tmp81 = inttoptr i64 %tmp80 to i64*
%tmp82 = load i64, i64* %tmp81, align 8
tail call void (i64, i32, ...) @llvm.experimental.stackmap(i64 14, i32 8, i64 %arg, i64 %tmp2, i64 %tmp10, i64 %tmp82)
tail call void (i64, i32, i8*, i32, ...) @llvm.experimental.patchpoint.void(i64 15, i32 32, i8* null, i32 3, i64 %arg, i64 %tmp10, i64 %tmp82)
%tmp83 = load i64, i64* %tmp33, align 8
%tmp84 = add i64 %tmp83, -24
%tmp85 = inttoptr i64 %tmp84 to i64*
%tmp86 = load i64, i64* %tmp85, align 8
tail call void (i64, i32, ...) @llvm.experimental.stackmap(i64 17, i32 8, i64 %arg, i64 %tmp10, i64 %tmp86)
tail call void (i64, i32, i8*, i32, ...) @llvm.experimental.patchpoint.void(i64 18, i32 32, i8* null, i32 3, i64 %arg, i64 %tmp10, i64 %tmp86)
ret i64 10
}
; Test small patchpoints that don't emit calls.
define void @small_patchpoint_codegen(i64 %p1, i64 %p2, i64 %p3, i64 %p4) {
entry:
; CHECK-LABEL: small_patchpoint_codegen:
; CHECK: Ltmp
; CHECK: nop
; CHECK-NEXT: nop
; CHECK-NEXT: nop
; CHECK-NEXT: nop
; CHECK-NEXT: nop
; CHECK-NEXT: ldp
; CHECK-NEXT: ret
%result = tail call i64 (i64, i32, i8*, i32, ...) @llvm.experimental.patchpoint.i64(i64 5, i32 20, i8* null, i32 2, i64 %p1, i64 %p2)
ret void
}
declare void @llvm.experimental.stackmap(i64, i32, ...)
declare void @llvm.experimental.patchpoint.void(i64, i32, i8*, i32, ...)
declare i64 @llvm.experimental.patchpoint.i64(i64, i32, i8*, i32, ...)