Add @earlyclobber constraints to the writeback register of all ARM store instructions.
The ARMARM specifies these instructions as unpredictable when storing the
writeback register. This shouldn't affect code generation much since storing a
pointer to itself is quite rare.
llvm-svn: 129409
diff --git a/llvm/lib/Target/ARM/ARMInstrInfo.td b/llvm/lib/Target/ARM/ARMInstrInfo.td
index d10f1f1..eb8f4aa 100644
--- a/llvm/lib/Target/ARM/ARMInstrInfo.td
+++ b/llvm/lib/Target/ARM/ARMInstrInfo.td
@@ -1802,41 +1802,47 @@
def STR_PRE : AI2stridx<0, 1, (outs GPR:$Rn_wb),
(ins GPR:$Rt, GPR:$Rn, am2offset:$offset),
IndexModePre, StFrm, IIC_iStore_ru,
- "str", "\t$Rt, [$Rn, $offset]!", "$Rn = $Rn_wb",
+ "str", "\t$Rt, [$Rn, $offset]!",
+ "$Rn = $Rn_wb,@earlyclobber $Rn_wb",
[(set GPR:$Rn_wb,
(pre_store GPR:$Rt, GPR:$Rn, am2offset:$offset))]>;
def STR_POST : AI2stridx<0, 0, (outs GPR:$Rn_wb),
(ins GPR:$Rt, GPR:$Rn, am2offset:$offset),
IndexModePost, StFrm, IIC_iStore_ru,
- "str", "\t$Rt, [$Rn], $offset", "$Rn = $Rn_wb",
+ "str", "\t$Rt, [$Rn], $offset",
+ "$Rn = $Rn_wb,@earlyclobber $Rn_wb",
[(set GPR:$Rn_wb,
(post_store GPR:$Rt, GPR:$Rn, am2offset:$offset))]>;
def STRB_PRE : AI2stridx<1, 1, (outs GPR:$Rn_wb),
(ins GPR:$Rt, GPR:$Rn, am2offset:$offset),
IndexModePre, StFrm, IIC_iStore_bh_ru,
- "strb", "\t$Rt, [$Rn, $offset]!", "$Rn = $Rn_wb",
+ "strb", "\t$Rt, [$Rn, $offset]!",
+ "$Rn = $Rn_wb,@earlyclobber $Rn_wb",
[(set GPR:$Rn_wb, (pre_truncsti8 GPR:$Rt,
GPR:$Rn, am2offset:$offset))]>;
def STRB_POST: AI2stridx<1, 0, (outs GPR:$Rn_wb),
(ins GPR:$Rt, GPR:$Rn, am2offset:$offset),
IndexModePost, StFrm, IIC_iStore_bh_ru,
- "strb", "\t$Rt, [$Rn], $offset", "$Rn = $Rn_wb",
+ "strb", "\t$Rt, [$Rn], $offset",
+ "$Rn = $Rn_wb,@earlyclobber $Rn_wb",
[(set GPR:$Rn_wb, (post_truncsti8 GPR:$Rt,
GPR:$Rn, am2offset:$offset))]>;
def STRH_PRE : AI3stridx<0b1011, 0, 1, (outs GPR:$Rn_wb),
(ins GPR:$Rt, GPR:$Rn, am3offset:$offset),
IndexModePre, StMiscFrm, IIC_iStore_ru,
- "strh", "\t$Rt, [$Rn, $offset]!", "$Rn = $Rn_wb",
+ "strh", "\t$Rt, [$Rn, $offset]!",
+ "$Rn = $Rn_wb,@earlyclobber $Rn_wb",
[(set GPR:$Rn_wb,
(pre_truncsti16 GPR:$Rt, GPR:$Rn, am3offset:$offset))]>;
def STRH_POST: AI3stridx<0b1011, 0, 0, (outs GPR:$Rn_wb),
(ins GPR:$Rt, GPR:$Rn, am3offset:$offset),
IndexModePost, StMiscFrm, IIC_iStore_bh_ru,
- "strh", "\t$Rt, [$Rn], $offset", "$Rn = $Rn_wb",
+ "strh", "\t$Rt, [$Rn], $offset",
+ "$Rn = $Rn_wb,@earlyclobber $Rn_wb",
[(set GPR:$Rn_wb, (post_truncsti16 GPR:$Rt,
GPR:$Rn, am3offset:$offset))]>;