Commit 844ec6bb authored by Russ Cox's avatar Russ Cox

cmd/8g: fix liveness for 387 build (including plan9)

TBR=khr
CC=golang-codereviews
https://golang.org/cl/84570045
parent 258ee61c
......@@ -138,11 +138,16 @@ static ProgInfo progtable[ALAST] = {
[AFMOVW]= {SizeW | LeftAddr | RightWrite},
[AFMOVV]= {SizeQ | LeftAddr | RightWrite},
[AFMOVDP]= {SizeD | LeftRead | RightAddr},
[AFMOVFP]= {SizeF | LeftRead | RightAddr},
[AFMOVLP]= {SizeL | LeftRead | RightAddr},
[AFMOVWP]= {SizeW | LeftRead | RightAddr},
[AFMOVVP]= {SizeQ | LeftRead | RightAddr},
// These instructions are marked as RightAddr
// so that the register optimizer does not try to replace the
// memory references with integer register references.
// But they do not use the previous value at the address, so
// we also mark them RightWrite.
[AFMOVDP]= {SizeD | LeftRead | RightWrite | RightAddr},
[AFMOVFP]= {SizeF | LeftRead | RightWrite | RightAddr},
[AFMOVLP]= {SizeL | LeftRead | RightWrite | RightAddr},
[AFMOVWP]= {SizeW | LeftRead | RightWrite | RightAddr},
[AFMOVVP]= {SizeQ | LeftRead | RightWrite | RightAddr},
[AFMULD]= {SizeD | LeftAddr | RightRdwr},
[AFMULDP]= {SizeD | LeftAddr | RightRdwr},
......
......@@ -755,7 +755,15 @@ Next:
if(prog->as == AVARDEF || prog->as == AVARKILL)
bvset(varkill, pos);
} else {
if(info.flags & (RightRead | RightAddr))
// RightRead is a read, obviously.
// RightAddr by itself is also implicitly a read.
//
// RightAddr|RightWrite means that the address is being taken
// but only so that the instruction can write to the value.
// It is not a read. It is equivalent to RightWrite except that
// having the RightAddr bit set keeps the registerizer from
// trying to substitute a register for the memory location.
if((info.flags & RightRead) || (info.flags & (RightAddr|RightWrite)) == RightAddr)
bvset(uevar, pos);
if(info.flags & RightWrite)
if(to->node != nil && (!isfat(to->node->type) || prog->as == AVARDEF))
......
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