cmd/compile: add restrictions on the shift amount range of arm64 various instructions

For arm64 constant shift instructions, e.g., LSL(immediate), they use
only the low 6 bits. To conform the semantics of the hardware instructions,
this CL comments in ARM64OPS.go about restricted AuxInt ranges for the
various instructions involved.

Change-Id: I2b6560d6580e22ba7cbfa744a02b046dd5714b8a
Reviewed-on: https://go-review.googlesource.com/c/go/+/303569
Trust: fannie zhang <Fannie.Zhang@arm.com>
Reviewed-by: Keith Randall <khr@golang.org>

1 files changed, 47 insertions, 46 deletions

diff --git a/src/cmd/compile/internal/ssa/gen/ARM64Ops.go b/src/cmd/compile/internal/ssa/gen/ARM64Ops.go
index 65e54202bf..18a5666b40 100644
--- a/src/cmd/compile/internal/ssa/gen/ARM64Ops.go
+++ b/src/cmd/compile/internal/ssa/gen/ARM64Ops.go
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build ignore
 // +build ignore
 
 package main
@@ -266,17 +267,17 @@ func init() {
 
 		// shifts
 		{name: "SLL", argLength: 2, reg: gp21, asm: "LSL"},                        // arg0 << arg1, shift amount is mod 64
-		{name: "SLLconst", argLength: 1, reg: gp11, asm: "LSL", aux: "Int64"},     // arg0 << auxInt
+		{name: "SLLconst", argLength: 1, reg: gp11, asm: "LSL", aux: "Int64"},     // arg0 << auxInt, auxInt should be in the range 0 to 63.
 		{name: "SRL", argLength: 2, reg: gp21, asm: "LSR"},                        // arg0 >> arg1, unsigned, shift amount is mod 64
-		{name: "SRLconst", argLength: 1, reg: gp11, asm: "LSR", aux: "Int64"},     // arg0 >> auxInt, unsigned
+		{name: "SRLconst", argLength: 1, reg: gp11, asm: "LSR", aux: "Int64"},     // arg0 >> auxInt, unsigned, auxInt should be in the range 0 to 63.
 		{name: "SRA", argLength: 2, reg: gp21, asm: "ASR"},                        // arg0 >> arg1, signed, shift amount is mod 64
-		{name: "SRAconst", argLength: 1, reg: gp11, asm: "ASR", aux: "Int64"},     // arg0 >> auxInt, signed
+		{name: "SRAconst", argLength: 1, reg: gp11, asm: "ASR", aux: "Int64"},     // arg0 >> auxInt, signed, auxInt should be in the range 0 to 63.
 		{name: "ROR", argLength: 2, reg: gp21, asm: "ROR"},                        // arg0 right rotate by (arg1 mod 64) bits
 		{name: "RORW", argLength: 2, reg: gp21, asm: "RORW"},                      // arg0 right rotate by (arg1 mod 32) bits
-		{name: "RORconst", argLength: 1, reg: gp11, asm: "ROR", aux: "Int64"},     // arg0 right rotate by auxInt bits
-		{name: "RORWconst", argLength: 1, reg: gp11, asm: "RORW", aux: "Int64"},   // uint32(arg0) right rotate by auxInt bits
-		{name: "EXTRconst", argLength: 2, reg: gp21, asm: "EXTR", aux: "Int64"},   // extract 64 bits from arg0:arg1 starting at lsb auxInt
-		{name: "EXTRWconst", argLength: 2, reg: gp21, asm: "EXTRW", aux: "Int64"}, // extract 32 bits from arg0[31:0]:arg1[31:0] starting at lsb auxInt and zero top 32 bits
+		{name: "RORconst", argLength: 1, reg: gp11, asm: "ROR", aux: "Int64"},     // arg0 right rotate by auxInt bits, auxInt should be in the range 0 to 63.
+		{name: "RORWconst", argLength: 1, reg: gp11, asm: "RORW", aux: "Int64"},   // uint32(arg0) right rotate by auxInt bits, auxInt should be in the range 0 to 31.
+		{name: "EXTRconst", argLength: 2, reg: gp21, asm: "EXTR", aux: "Int64"},   // extract 64 bits from arg0:arg1 starting at lsb auxInt, auxInt should be in the range 0 to 63.
+		{name: "EXTRWconst", argLength: 2, reg: gp21, asm: "EXTRW", aux: "Int64"}, // extract 32 bits from arg0[31:0]:arg1[31:0] starting at lsb auxInt and zero top 32 bits, auxInt should be in the range 0 to 31.
 
 		// comparisons
 		{name: "CMP", argLength: 2, reg: gp2flags, asm: "CMP", typ: "Flags"},                      // arg0 compare to arg1
@@ -297,45 +298,45 @@ func init() {
 		{name: "FCMPD0", argLength: 1, reg: fp1flags, asm: "FCMPD", typ: "Flags"},                 // arg0 compare to 0, float64
 
 		// shifted ops
-		{name: "MVNshiftLL", argLength: 1, reg: gp11, asm: "MVN", aux: "Int64"},                   // ^(arg0<<auxInt)
-		{name: "MVNshiftRL", argLength: 1, reg: gp11, asm: "MVN", aux: "Int64"},                   // ^(arg0>>auxInt), unsigned shift
-		{name: "MVNshiftRA", argLength: 1, reg: gp11, asm: "MVN", aux: "Int64"},                   // ^(arg0>>auxInt), signed shift
-		{name: "NEGshiftLL", argLength: 1, reg: gp11, asm: "NEG", aux: "Int64"},                   // -(arg0<<auxInt)
-		{name: "NEGshiftRL", argLength: 1, reg: gp11, asm: "NEG", aux: "Int64"},                   // -(arg0>>auxInt), unsigned shift
-		{name: "NEGshiftRA", argLength: 1, reg: gp11, asm: "NEG", aux: "Int64"},                   // -(arg0>>auxInt), signed shift
-		{name: "ADDshiftLL", argLength: 2, reg: gp21, asm: "ADD", aux: "Int64"},                   // arg0 + arg1<<auxInt
-		{name: "ADDshiftRL", argLength: 2, reg: gp21, asm: "ADD", aux: "Int64"},                   // arg0 + arg1>>auxInt, unsigned shift
-		{name: "ADDshiftRA", argLength: 2, reg: gp21, asm: "ADD", aux: "Int64"},                   // arg0 + arg1>>auxInt, signed shift
-		{name: "SUBshiftLL", argLength: 2, reg: gp21, asm: "SUB", aux: "Int64"},                   // arg0 - arg1<<auxInt
-		{name: "SUBshiftRL", argLength: 2, reg: gp21, asm: "SUB", aux: "Int64"},                   // arg0 - arg1>>auxInt, unsigned shift
-		{name: "SUBshiftRA", argLength: 2, reg: gp21, asm: "SUB", aux: "Int64"},                   // arg0 - arg1>>auxInt, signed shift
-		{name: "ANDshiftLL", argLength: 2, reg: gp21, asm: "AND", aux: "Int64"},                   // arg0 & (arg1<<auxInt)
-		{name: "ANDshiftRL", argLength: 2, reg: gp21, asm: "AND", aux: "Int64"},                   // arg0 & (arg1>>auxInt), unsigned shift
-		{name: "ANDshiftRA", argLength: 2, reg: gp21, asm: "AND", aux: "Int64"},                   // arg0 & (arg1>>auxInt), signed shift
-		{name: "ORshiftLL", argLength: 2, reg: gp21, asm: "ORR", aux: "Int64"},                    // arg0 | arg1<<auxInt
-		{name: "ORshiftRL", argLength: 2, reg: gp21, asm: "ORR", aux: "Int64"},                    // arg0 | arg1>>auxInt, unsigned shift
-		{name: "ORshiftRA", argLength: 2, reg: gp21, asm: "ORR", aux: "Int64"},                    // arg0 | arg1>>auxInt, signed shift
-		{name: "XORshiftLL", argLength: 2, reg: gp21, asm: "EOR", aux: "Int64"},                   // arg0 ^ arg1<<auxInt
-		{name: "XORshiftRL", argLength: 2, reg: gp21, asm: "EOR", aux: "Int64"},                   // arg0 ^ arg1>>auxInt, unsigned shift
-		{name: "XORshiftRA", argLength: 2, reg: gp21, asm: "EOR", aux: "Int64"},                   // arg0 ^ arg1>>auxInt, signed shift
-		{name: "BICshiftLL", argLength: 2, reg: gp21, asm: "BIC", aux: "Int64"},                   // arg0 &^ (arg1<<auxInt)
-		{name: "BICshiftRL", argLength: 2, reg: gp21, asm: "BIC", aux: "Int64"},                   // arg0 &^ (arg1>>auxInt), unsigned shift
-		{name: "BICshiftRA", argLength: 2, reg: gp21, asm: "BIC", aux: "Int64"},                   // arg0 &^ (arg1>>auxInt), signed shift
-		{name: "EONshiftLL", argLength: 2, reg: gp21, asm: "EON", aux: "Int64"},                   // arg0 ^ ^(arg1<<auxInt)
-		{name: "EONshiftRL", argLength: 2, reg: gp21, asm: "EON", aux: "Int64"},                   // arg0 ^ ^(arg1>>auxInt), unsigned shift
-		{name: "EONshiftRA", argLength: 2, reg: gp21, asm: "EON", aux: "Int64"},                   // arg0 ^ ^(arg1>>auxInt), signed shift
-		{name: "ORNshiftLL", argLength: 2, reg: gp21, asm: "ORN", aux: "Int64"},                   // arg0 | ^(arg1<<auxInt)
-		{name: "ORNshiftRL", argLength: 2, reg: gp21, asm: "ORN", aux: "Int64"},                   // arg0 | ^(arg1>>auxInt), unsigned shift
-		{name: "ORNshiftRA", argLength: 2, reg: gp21, asm: "ORN", aux: "Int64"},                   // arg0 | ^(arg1>>auxInt), signed shift
-		{name: "CMPshiftLL", argLength: 2, reg: gp2flags, asm: "CMP", aux: "Int64", typ: "Flags"}, // arg0 compare to arg1<<auxInt
-		{name: "CMPshiftRL", argLength: 2, reg: gp2flags, asm: "CMP", aux: "Int64", typ: "Flags"}, // arg0 compare to arg1>>auxInt, unsigned shift
-		{name: "CMPshiftRA", argLength: 2, reg: gp2flags, asm: "CMP", aux: "Int64", typ: "Flags"}, // arg0 compare to arg1>>auxInt, signed shift
-		{name: "CMNshiftLL", argLength: 2, reg: gp2flags, asm: "CMN", aux: "Int64", typ: "Flags"}, // (arg0 + arg1<<auxInt) compare to 0
-		{name: "CMNshiftRL", argLength: 2, reg: gp2flags, asm: "CMN", aux: "Int64", typ: "Flags"}, // (arg0 + arg1>>auxInt) compare to 0, unsigned shift
-		{name: "CMNshiftRA", argLength: 2, reg: gp2flags, asm: "CMN", aux: "Int64", typ: "Flags"}, // (arg0 + arg1>>auxInt) compare to 0, signed shift
-		{name: "TSTshiftLL", argLength: 2, reg: gp2flags, asm: "TST", aux: "Int64", typ: "Flags"}, // (arg0 & arg1<<auxInt) compare to 0
-		{name: "TSTshiftRL", argLength: 2, reg: gp2flags, asm: "TST", aux: "Int64", typ: "Flags"}, // (arg0 & arg1>>auxInt) compare to 0, unsigned shift
-		{name: "TSTshiftRA", argLength: 2, reg: gp2flags, asm: "TST", aux: "Int64", typ: "Flags"}, // (arg0 & arg1>>auxInt) compare to 0, signed shift
+		{name: "MVNshiftLL", argLength: 1, reg: gp11, asm: "MVN", aux: "Int64"},                   // ^(arg0<<auxInt), auxInt should be in the range 0 to 63.
+		{name: "MVNshiftRL", argLength: 1, reg: gp11, asm: "MVN", aux: "Int64"},                   // ^(arg0>>auxInt), unsigned shift, auxInt should be in the range 0 to 63.
+		{name: "MVNshiftRA", argLength: 1, reg: gp11, asm: "MVN", aux: "Int64"},                   // ^(arg0>>auxInt), signed shift, auxInt should be in the range 0 to 63.
+		{name: "NEGshiftLL", argLength: 1, reg: gp11, asm: "NEG", aux: "Int64"},                   // -(arg0<<auxInt), auxInt should be in the range 0 to 63.
+		{name: "NEGshiftRL", argLength: 1, reg: gp11, asm: "NEG", aux: "Int64"},                   // -(arg0>>auxInt), unsigned shift, auxInt should be in the range 0 to 63.
+		{name: "NEGshiftRA", argLength: 1, reg: gp11, asm: "NEG", aux: "Int64"},                   // -(arg0>>auxInt), signed shift, auxInt should be in the range 0 to 63.
+		{name: "ADDshiftLL", argLength: 2, reg: gp21, asm: "ADD", aux: "Int64"},                   // arg0 + arg1<<auxInt, auxInt should be in the range 0 to 63.
+		{name: "ADDshiftRL", argLength: 2, reg: gp21, asm: "ADD", aux: "Int64"},                   // arg0 + arg1>>auxInt, unsigned shift, auxInt should be in the range 0 to 63.
+		{name: "ADDshiftRA", argLength: 2, reg: gp21, asm: "ADD", aux: "Int64"},                   // arg0 + arg1>>auxInt, signed shift, auxInt should be in the range 0 to 63.
+		{name: "SUBshiftLL", argLength: 2, reg: gp21, asm: "SUB", aux: "Int64"},                   // arg0 - arg1<<auxInt, auxInt should be in the range 0 to 63.
+		{name: "SUBshiftRL", argLength: 2, reg: gp21, asm: "SUB", aux: "Int64"},                   // arg0 - arg1>>auxInt, unsigned shift, auxInt should be in the range 0 to 63.
+		{name: "SUBshiftRA", argLength: 2, reg: gp21, asm: "SUB", aux: "Int64"},                   // arg0 - arg1>>auxInt, signed shift, auxInt should be in the range 0 to 63.
+		{name: "ANDshiftLL", argLength: 2, reg: gp21, asm: "AND", aux: "Int64"},                   // arg0 & (arg1<<auxInt), auxInt should be in the range 0 to 63.
+		{name: "ANDshiftRL", argLength: 2, reg: gp21, asm: "AND", aux: "Int64"},                   // arg0 & (arg1>>auxInt), unsigned shift, auxInt should be in the range 0 to 63.
+		{name: "ANDshiftRA", argLength: 2, reg: gp21, asm: "AND", aux: "Int64"},                   // arg0 & (arg1>>auxInt), signed shift, auxInt should be in the range 0 to 63.
+		{name: "ORshiftLL", argLength: 2, reg: gp21, asm: "ORR", aux: "Int64"},                    // arg0 | arg1<<auxInt, auxInt should be in the range 0 to 63.
+		{name: "ORshiftRL", argLength: 2, reg: gp21, asm: "ORR", aux: "Int64"},                    // arg0 | arg1>>auxInt, unsigned shift, auxInt should be in the range 0 to 63.
+		{name: "ORshiftRA", argLength: 2, reg: gp21, asm: "ORR", aux: "Int64"},                    // arg0 | arg1>>auxInt, signed shift, auxInt should be in the range 0 to 63.
+		{name: "XORshiftLL", argLength: 2, reg: gp21, asm: "EOR", aux: "Int64"},                   // arg0 ^ arg1<<auxInt, auxInt should be in the range 0 to 63.
+		{name: "XORshiftRL", argLength: 2, reg: gp21, asm: "EOR", aux: "Int64"},                   // arg0 ^ arg1>>auxInt, unsigned shift, auxInt should be in the range 0 to 63.
+		{name: "XORshiftRA", argLength: 2, reg: gp21, asm: "EOR", aux: "Int64"},                   // arg0 ^ arg1>>auxInt, signed shift, auxInt should be in the range 0 to 63.
+		{name: "BICshiftLL", argLength: 2, reg: gp21, asm: "BIC", aux: "Int64"},                   // arg0 &^ (arg1<<auxInt), auxInt should be in the range 0 to 63.
+		{name: "BICshiftRL", argLength: 2, reg: gp21, asm: "BIC", aux: "Int64"},                   // arg0 &^ (arg1>>auxInt), unsigned shift, auxInt should be in the range 0 to 63.
+		{name: "BICshiftRA", argLength: 2, reg: gp21, asm: "BIC", aux: "Int64"},                   // arg0 &^ (arg1>>auxInt), signed shift, auxInt should be in the range 0 to 63.
+		{name: "EONshiftLL", argLength: 2, reg: gp21, asm: "EON", aux: "Int64"},                   // arg0 ^ ^(arg1<<auxInt), auxInt should be in the range 0 to 63.
+		{name: "EONshiftRL", argLength: 2, reg: gp21, asm: "EON", aux: "Int64"},                   // arg0 ^ ^(arg1>>auxInt), unsigned shift, auxInt should be in the range 0 to 63.
+		{name: "EONshiftRA", argLength: 2, reg: gp21, asm: "EON", aux: "Int64"},                   // arg0 ^ ^(arg1>>auxInt), signed shift, auxInt should be in the range 0 to 63.
+		{name: "ORNshiftLL", argLength: 2, reg: gp21, asm: "ORN", aux: "Int64"},                   // arg0 | ^(arg1<<auxInt), auxInt should be in the range 0 to 63.
+		{name: "ORNshiftRL", argLength: 2, reg: gp21, asm: "ORN", aux: "Int64"},                   // arg0 | ^(arg1>>auxInt), unsigned shift, auxInt should be in the range 0 to 63.
+		{name: "ORNshiftRA", argLength: 2, reg: gp21, asm: "ORN", aux: "Int64"},                   // arg0 | ^(arg1>>auxInt), signed shift, auxInt should be in the range 0 to 63.
+		{name: "CMPshiftLL", argLength: 2, reg: gp2flags, asm: "CMP", aux: "Int64", typ: "Flags"}, // arg0 compare to arg1<<auxInt, auxInt should be in the range 0 to 63.
+		{name: "CMPshiftRL", argLength: 2, reg: gp2flags, asm: "CMP", aux: "Int64", typ: "Flags"}, // arg0 compare to arg1>>auxInt, unsigned shift, auxInt should be in the range 0 to 63.
+		{name: "CMPshiftRA", argLength: 2, reg: gp2flags, asm: "CMP", aux: "Int64", typ: "Flags"}, // arg0 compare to arg1>>auxInt, signed shift, auxInt should be in the range 0 to 63.
+		{name: "CMNshiftLL", argLength: 2, reg: gp2flags, asm: "CMN", aux: "Int64", typ: "Flags"}, // (arg0 + arg1<<auxInt) compare to 0, auxInt should be in the range 0 to 63.
+		{name: "CMNshiftRL", argLength: 2, reg: gp2flags, asm: "CMN", aux: "Int64", typ: "Flags"}, // (arg0 + arg1>>auxInt) compare to 0, unsigned shift, auxInt should be in the range 0 to 63.
+		{name: "CMNshiftRA", argLength: 2, reg: gp2flags, asm: "CMN", aux: "Int64", typ: "Flags"}, // (arg0 + arg1>>auxInt) compare to 0, signed shift, auxInt should be in the range 0 to 63.
+		{name: "TSTshiftLL", argLength: 2, reg: gp2flags, asm: "TST", aux: "Int64", typ: "Flags"}, // (arg0 & arg1<<auxInt) compare to 0, auxInt should be in the range 0 to 63.
+		{name: "TSTshiftRL", argLength: 2, reg: gp2flags, asm: "TST", aux: "Int64", typ: "Flags"}, // (arg0 & arg1>>auxInt) compare to 0, unsigned shift, auxInt should be in the range 0 to 63.
+		{name: "TSTshiftRA", argLength: 2, reg: gp2flags, asm: "TST", aux: "Int64", typ: "Flags"}, // (arg0 & arg1>>auxInt) compare to 0, signed shift, auxInt should be in the range 0 to 63.
 
 		// bitfield ops
 		// for all bitfield ops lsb is auxInt>>8, width is auxInt&0xff