RPCS3/llvm
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm.git synced 2024-12-28 07:05:03 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

ARM: add constraint that RdLo != Rn != RdHi for v5 MLA insts.

Browse Source 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199212 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Tim Northover 2014-01-14 13:05:47 +00:00
parent 6e533d710d
commit 6849f102ca
2 changed files with 28 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
lib/Target/ARM/ARMInstrInfo.td
View File

@ -3714,7 +3714,8 @@ def UMAAL : AMul1I <0b0000010, (outs GPR:$RdLo, GPR:$RdHi),
let Inst{3-0} = Rn;
}
let Constraints = "$RLo = $RdLo,$RHi = $RdHi" in {
let Constraints =
"@earlyclobber $RdLo,@earlyclobber $RdHi,$RLo = $RdLo,$RHi = $RdHi" in {
def SMLALv5 : ARMPseudoExpand<(outs GPR:$RdLo, GPR:$RdHi),
(ins GPR:$Rn, GPR:$Rm, GPR:$RLo, GPR:$RHi, pred:$p, cc_out:$s),
4, IIC_iMAC64, [],

26
test/CodeGen/ARM/longMAC.ll
View File

@ -1,4 +1,5 @@
; RUN: llc < %s -march=arm | FileCheck %s
; RUN: llc < %s -mtriple=armv7 | FileCheck %s --check-prefix=CHECK-V7
; Check generated signed and unsigned multiply accumulate long.
define i64 @MACLongTest1(i32 %a, i32 %b, i64 %c) {
@ -42,3 +43,28 @@ define i64 @MACLongTest4(i32 %a, i32 %b, i32 %c) {
%add = add nsw i64 %mul, %conv2
ret i64 %add
}
; Two things to check here: the @earlyclobber constraint (on <= v5) and the "$Rd = $R" ones.
; + Without @earlyclobber the v7 code is natural. With it, the first two
; registers must be distinct from the third.
; + Without "$Rd = $R", this can be satisfied without a mov before the umlal
; by trying to use 6 different registers in the MachineInstr. The natural
; evolution of this attempt currently leaves only two movs in the final
; function, both after the umlal. With it, *some* move has to happen
; before the umlal.
define i64 @MACLongTest5(i64 %c, i32 %a, i32 %b) {
; CHECK-V7-LABEL: MACLongTest5:
; CHECK-V7-LABEL: umlal r0, r1, r0, r0
; CHECK-LABEL: MACLongTest5:
; CHECK: mov [[RDLO:r[0-9]+]], r0
; CHECK: umlal [[RDLO]], r1, r0, r0
; CHECK: mov r0, [[RDLO]]
%conv.trunc = trunc i64 %c to i32
%conv = zext i32 %conv.trunc to i64
%conv1 = zext i32 %b to i64
%mul = mul i64 %conv, %conv
%add = add i64 %mul, %c
ret i64 %add
}