From 03eb0e3c3357f09c4b710d43bac04e8f02870341 Mon Sep 17 00:00:00 2001 From: Evan Cheng Date: Tue, 4 Aug 2009 01:41:15 +0000 Subject: Emit sub r, #c instead of transforming it to add r, #-c if c fits in 8-bit. This is a bit of pre-mature optimization. 8-bit variant makes it likely it will be narrowed to a 16-bit instruction. llvm-svn: 78030 --- llvm/lib/Target/ARM/ARMInstrThumb2.td | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) (limited to 'llvm/lib/Target/ARM') diff --git a/llvm/lib/Target/ARM/ARMInstrThumb2.td b/llvm/lib/Target/ARM/ARMInstrThumb2.td index 8c562b04355..faa7dd5475d 100644 --- a/llvm/lib/Target/ARM/ARMInstrThumb2.td +++ b/llvm/lib/Target/ARM/ARMInstrThumb2.td @@ -83,6 +83,10 @@ def imm0_4095_neg : PatLeaf<(i32 imm), [{ return (uint32_t)(-N->getZExtValue()) < 4096; }], imm_neg_XFORM>; +def imm0_255_neg : PatLeaf<(i32 imm), [{ + return (uint32_t)(-N->getZExtValue()) < 255; +}], imm_neg_XFORM>; + /// imm0_65535 predicate - True if the 32-bit immediate is in the range /// [0.65535]. def imm0_65535 : PatLeaf<(i32 imm), [{ @@ -619,12 +623,12 @@ def t2STRB_POST : T2Iidxldst<(outs GPR:$base_wb), let mayLoad = 1 in def t2LDM : T2XI<(outs), (ins addrmode4:$addr, pred:$p, reglist:$dst1, variable_ops), - "ldm${addr:submode}${p}.w $addr, $dst1", []>; + "ldm${addr:submode}${p} $addr, $dst1", []>; let mayStore = 1 in def t2STM : T2XI<(outs), (ins addrmode4:$addr, pred:$p, reglist:$src1, variable_ops), - "stm${addr:submode}${p}.w $addr, $src1", []>; + "stm${addr:submode}${p} $addr, $src1", []>; //===----------------------------------------------------------------------===// // Move Instructions. @@ -704,6 +708,9 @@ defm t2RSB : T2I_rbin_is <"rsb", BinOpFrag<(sub node:$LHS, node:$RHS)>>; defm t2RSBS : T2I_rbin_s_is <"rsb", BinOpFrag<(subc node:$LHS, node:$RHS)>>; // (sub X, imm) gets canonicalized to (add X, -imm). Match this form. +let AddedComplexity = 1 in +def : T2Pat<(add GPR:$src, imm0_255_neg:$imm), + (t2SUBri GPR:$src, imm0_255_neg:$imm)>; def : T2Pat<(add GPR:$src, t2_so_imm_neg:$imm), (t2SUBri GPR:$src, t2_so_imm_neg:$imm)>; def : T2Pat<(add GPR:$src, imm0_4095_neg:$imm), -- cgit v1.2.3