llvm/test/CodeGen/WebAssembly/varargs.ll
Dan Gohman 1a513a6964 [WebAssembly] Optimize away return instructions using fallthroughs.
This saves a small amount of code size, and is a first small step toward
passing values on the stack across block boundaries.

Differential Review: http://reviews.llvm.org/D20450


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@270294 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-21 00:21:56 +00:00

153 lines
4.1 KiB
LLVM

; RUN: llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -verify-machineinstrs | FileCheck %s
; Test varargs constructs.
target datalayout = "e-m:e-p:32:32-i64:64-n32:64-S128"
target triple = "wasm32-unknown-unknown"
; Test va_start.
; TODO: Test va_start.
; CHECK-LABEL: start:
; CHECK-NEXT: .param i32, i32
; CHECK-NOT: __stack_pointer
define void @start(i8** %ap, ...) {
entry:
%0 = bitcast i8** %ap to i8*
; Store the second argument (the hidden vararg buffer pointer) into ap
; CHECK: i32.store $drop=, 0($0), $1
call void @llvm.va_start(i8* %0)
ret void
}
; Test va_end.
; CHECK-LABEL: end:
; CHECK-NEXT: .param i32{{$}}
; CHECK-NEXT: return{{$}}
define void @end(i8** %ap) {
entry:
%0 = bitcast i8** %ap to i8*
call void @llvm.va_end(i8* %0)
ret void
}
; Test va_copy.
; CHECK-LABEL: copy:
; CHECK-NEXT: .param i32, i32{{$}}
; CHECK-NEXT: i32.load $push0=, 0($1){{$}}
; CHECK-NEXT: i32.store $drop=, 0($0), $pop0{{$}}
; CHECK-NEXT: return{{$}}
define void @copy(i8** %ap, i8** %bp) {
entry:
%0 = bitcast i8** %ap to i8*
%1 = bitcast i8** %bp to i8*
call void @llvm.va_copy(i8* %0, i8* %1)
ret void
}
; Test va_arg with an i8 argument.
; CHECK-LABEL: arg_i8:
; CHECK-NEXT: .param i32{{$}}
; CHECK-NEXT: .result i32{{$}}
; CHECK-NEXT: .local i32{{$}}
; CHECK-NEXT: i32.load $push[[NUM0:[0-9]+]]=, 0($0){{$}}
; CHECK-NEXT: tee_local $push[[NUM1:[0-9]+]]=, $1=, $pop[[NUM0]]{{$}}
; CHECK-NEXT: i32.const $push[[NUM2:[0-9]+]]=, 4{{$}}
; CHECK-NEXT: i32.add $push[[NUM3:[0-9]+]]=, $pop[[NUM1]], $pop[[NUM2]]{{$}}
; CHECK-NEXT: i32.store $drop=, 0($0), $pop[[NUM3]]{{$}}
; CHECK-NEXT: i32.load $push[[NUM4:[0-9]+]]=, 0($1){{$}}
; CHECK-NEXT: return $pop[[NUM4]]{{$}}
define i8 @arg_i8(i8** %ap) {
entry:
%t = va_arg i8** %ap, i8
ret i8 %t
}
; Test va_arg with an i32 argument.
; CHECK-LABEL: arg_i32:
; CHECK-NEXT: .param i32{{$}}
; CHECK-NEXT: .result i32{{$}}
; CHECK-NEXT: .local i32{{$}}
; CHECK-NEXT: i32.load $push[[NUM0:[0-9]+]]=, 0($0){{$}}
; CHECK-NEXT: i32.const $push[[NUM1:[0-9]+]]=, 3{{$}}
; CHECK-NEXT: i32.add $push[[NUM2:[0-9]+]]=, $pop[[NUM0]], $pop[[NUM1]]{{$}}
; CHECK-NEXT: i32.const $push[[NUM3:[0-9]+]]=, -4{{$}}
; CHECK-NEXT: i32.and $push[[NUM4:[0-9]+]]=, $pop[[NUM2]], $pop[[NUM3]]{{$}}
; CHECK-NEXT: tee_local $push[[NUM5:[0-9]+]]=, $1=, $pop[[NUM4]]{{$}}
; CHECK-NEXT: i32.const $push[[NUM6:[0-9]+]]=, 4{{$}}
; CHECK-NEXT: i32.add $push[[NUM7:[0-9]+]]=, $pop[[NUM5]], $pop[[NUM6]]{{$}}
; CHECK-NEXT: i32.store $drop=, 0($0), $pop[[NUM7]]{{$}}
; CHECK-NEXT: i32.load $push[[NUM8:[0-9]+]]=, 0($1){{$}}
; CHECK-NEXT: return $pop[[NUM8]]{{$}}
define i32 @arg_i32(i8** %ap) {
entry:
%t = va_arg i8** %ap, i32
ret i32 %t
}
; Test va_arg with an i128 argument.
; CHECK-LABEL: arg_i128:
; CHECK-NEXT: .param i32, i32{{$}}
; CHECK-NEXT: .local
; CHECK: i32.and
; CHECK: i64.load
; CHECK: i64.load
; CHECK: return{{$}}
define i128 @arg_i128(i8** %ap) {
entry:
%t = va_arg i8** %ap, i128
ret i128 %t
}
; Test a varargs call with no actual arguments.
declare void @callee(...)
; CHECK-LABEL: caller_none:
; CHECK-NEXT: i32.const $push0=, 0
; CHECK-NEXT: call callee@FUNCTION, $pop0
; CHECK-NEXT: return{{$}}
define void @caller_none() {
call void (...) @callee()
ret void
}
; Test a varargs call with some actual arguments.
; Note that the store of 2.0 is converted to an i64 store; this optimization
; is not needed on WebAssembly, but there isn't currently a convenient hook for
; disabling it.
; CHECK-LABEL: caller_some
; CHECK: i32.store
; CHECK: i64.store
define void @caller_some() {
call void (...) @callee(i32 0, double 2.0)
ret void
}
; Test a va_start call in a non-entry block
; CHECK-LABEL: startbb:
; CHECK: .param i32, i32, i32
define void @startbb(i1 %cond, i8** %ap, ...) {
entry:
br i1 %cond, label %bb0, label %bb1
bb0:
ret void
bb1:
%0 = bitcast i8** %ap to i8*
; Store the second argument (the hidden vararg buffer pointer) into ap
; CHECK: i32.store $drop=, 0($1), $2
call void @llvm.va_start(i8* %0)
ret void
}
declare void @llvm.va_start(i8*)
declare void @llvm.va_end(i8*)
declare void @llvm.va_copy(i8*, i8*)