From f72ea8eb7624a15bc211bb5189169090013b2911 Mon Sep 17 00:00:00 2001
From: Kai Backman <kaib@golang.org>
Date: Wed, 14 Oct 2009 21:47:08 -0700
Subject: [PATCH] LDREX and STREX

R=rsc
APPROVED=rsc
DELTA=30  (30 added, 0 deleted, 0 changed)
OCL=35751
CL=35756
---
 src/cmd/5a/lex.c   |  3 +++
 src/cmd/5l/5.out.h |  3 +++
 src/cmd/5l/asm.c   | 19 +++++++++++++++++++
 src/cmd/5l/optab.c |  2 ++
 src/cmd/5l/span.c  |  3 +++
 5 files changed, 30 insertions(+)

diff --git a/src/cmd/5a/lex.c b/src/cmd/5a/lex.c
index c5e9a3e786..44ce3bb403 100644
--- a/src/cmd/5a/lex.c
+++ b/src/cmd/5a/lex.c
@@ -359,6 +359,9 @@ struct
 	"MOVWD",	LTYPE3, AMOVWD,
 	"MOVWF",		LTYPE3, AMOVWF,
 
+	"LDREX",		LTYPE3, ALDREX,
+	"STREX",		LTYPE9, ASTREX,
+
 /*
 	"ABSF",		LTYPEI, AABSF,
 	"ABSD",		LTYPEI, AABSD,
diff --git a/src/cmd/5l/5.out.h b/src/cmd/5l/5.out.h
index f78b3f6b73..07f0596fbd 100644
--- a/src/cmd/5l/5.out.h
+++ b/src/cmd/5l/5.out.h
@@ -176,6 +176,9 @@ enum	as
 
 	ASIGNAME,
 
+	ALDREX,
+	ASTREX,
+
 	ALAST,
 };
 
diff --git a/src/cmd/5l/asm.c b/src/cmd/5l/asm.c
index 1abf07bbec..6cd4b2390c 100644
--- a/src/cmd/5l/asm.c
+++ b/src/cmd/5l/asm.c
@@ -1706,6 +1706,25 @@ if(debug['G']) print("%ulx: %s: arm %d %d %d %d\n", (uint32)(p->pc), p->from.sym
 		// o1 = olr(instoffset, p->to.reg, REGTMP, p->scond);	// mov O(R), Rtmp
 		o1 = ((p->scond&C_SCOND)<<28) | (0x12fff<<8) | (1<<4) | p->to.reg;		// BX R
 		break;
+	case 77:	/* ldrex oreg,reg */
+		aclass(&p->from);
+		if(instoffset != 0)
+			diag("offset must be zero in LDREX");
+		o1 = (0x19<<20) | (0xf9f);
+		o1 |= p->from.reg << 16;
+		o1 |= p->to.reg << 12;
+		o1 |= (p->scond & C_SCOND) << 28;
+		break;
+	case 78:	/* strex reg,oreg,reg */
+		aclass(&p->from);
+		if(instoffset != 0)
+			diag("offset must be zero in STREX");
+		o1 = (0x3<<23) | (0xf9<<4);
+		o1 |= p->from.reg << 16;
+		o1 |= p->reg << 0;
+		o1 |= p->to.reg << 12;
+		o1 |= (p->scond & C_SCOND) << 28;
+		break;
 	}
 
 	v = p->pc;
diff --git a/src/cmd/5l/optab.c b/src/cmd/5l/optab.c
index 88067c4b0a..92fe12fc29 100644
--- a/src/cmd/5l/optab.c
+++ b/src/cmd/5l/optab.c
@@ -281,6 +281,8 @@ Optab	optab[] =
 	{ AMOVHU,	C_LEXT,	C_NONE,	C_REG,		73, 8, REGSB,	LFROM|V4 },
 	{ AMOVHU,	C_LAUTO,C_NONE, C_REG,		73, 8, REGSP,	LFROM|V4 },
 	{ AMOVHU,	C_LOREG,C_NONE,	C_REG,		73, 8, 0,	LFROM|V4 },
+	{ ALDREX,	C_SOREG,C_NONE,	C_REG,		77, 4, 0 },
+	{ ASTREX,	C_SOREG,C_REG,	C_REG,		78, 4, 0 },
 
 	{ AXXX,		C_NONE,	C_NONE,	C_NONE,		 0, 4, 0 },
 };
diff --git a/src/cmd/5l/span.c b/src/cmd/5l/span.c
index 72121bf32d..1272b05ecc 100644
--- a/src/cmd/5l/span.c
+++ b/src/cmd/5l/span.c
@@ -1095,6 +1095,9 @@ buildop(void)
 			oprange[AMULLU] = oprange[r];
 			oprange[AMULALU] = oprange[r];
 			break;
+		case ALDREX:
+		case ASTREX:
+			break;
 		}
 	}
 }