llvm-6502/test/CodeGen/ARM/fptoint.ll
Tim Northover d0dbe02fd2 ARM & AArch64: make use of common cmpxchg idioms after expansion
The C and C++ semantics for compare_exchange require it to return a bool
indicating success. This gets mapped to LLVM IR which follows each cmpxchg with
an icmp of the value loaded against the desired value.

When lowered to ldxr/stxr loops, this extra comparison is redundant: its
results are implicit in the control-flow of the function.

This commit makes two changes: it replaces that icmp with appropriate PHI
nodes, and then makes sure earlyCSE is called after expansion to actually make
use of the opportunities revealed.

I've also added -{arm,aarch64}-enable-atomic-tidy options, so that
existing fragile tests aren't perturbed too much by the change. Many
of them either rely on undef/unreachable too pervasively to be
restored to something well-defined (particularly while making sure
they test the same obscure assert from many years ago), or depend on a
particular CFG shape, which is disrupted by SimplifyCFG.

rdar://problem/16227836

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209883 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-30 10:09:59 +00:00

50 lines
967 B
LLVM

; RUN: llc -mtriple=arm-eabi -arm-atomic-cfg-tidy=0 -mattr=+v6,+vfp2 %s -o - | FileCheck %s
@i = weak global i32 0 ; <i32*> [#uses=2]
@u = weak global i32 0 ; <i32*> [#uses=2]
define i32 @foo1(float *%x) {
%tmp1 = load float* %x
%tmp2 = bitcast float %tmp1 to i32
ret i32 %tmp2
}
define i64 @foo2(double *%x) {
%tmp1 = load double* %x
%tmp2 = bitcast double %tmp1 to i64
ret i64 %tmp2
}
define void @foo5(float %x) {
%tmp1 = fptosi float %x to i32
store i32 %tmp1, i32* @i
ret void
}
define void @foo6(float %x) {
%tmp1 = fptoui float %x to i32
store i32 %tmp1, i32* @u
ret void
}
define void @foo7(double %x) {
%tmp1 = fptosi double %x to i32
store i32 %tmp1, i32* @i
ret void
}
define void @foo8(double %x) {
%tmp1 = fptoui double %x to i32
store i32 %tmp1, i32* @u
ret void
}
define void @foo9(double %x) {
%tmp = fptoui double %x to i16
store i16 %tmp, i16* null
ret void
}
; CHECK-LABEL: foo9:
; CHECK: vmov r0, s0