cmd/internal/obj/arm64: fix incorrect rejection of legal instructions
"BFI $0, R1, $7, R2" is expected to copy bit 0~6 from R1 to R2, and
left R2's other bits unchanged.
But the assembler rejects it with error "illegal bit number", and
BFIW/SBFIZ/SBFIZW/UBFIZ/UBFIZW have the same problem.
This CL fixes that issue and adds corresponding test cases.
fixes #26736
Change-Id: Ie0090a0faa38a49dd9b096a0f435987849800b76
Reviewed-on: https://go-review.googlesource.com/127159
Run-TryBot: Ben Shi <powerman1st@163.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
diff --git a/src/cmd/asm/internal/asm/testdata/arm64.s b/src/cmd/asm/internal/asm/testdata/arm64.s
index 859f71a..3a4410f 100644
--- a/src/cmd/asm/internal/asm/testdata/arm64.s
+++ b/src/cmd/asm/internal/asm/testdata/arm64.s
@@ -716,6 +716,14 @@
STPW (R3, R4), x(SB)
STPW (R3, R4), x+8(SB)
+// bit field operation
+ BFI $0, R1, $1, R2 // 220040b3
+ BFIW $0, R1, $1, R2 // 22000033
+ SBFIZ $0, R1, $1, R2 // 22004093
+ SBFIZW $0, R1, $1, R2 // 22000013
+ UBFIZ $0, R1, $1, R2 // 220040d3
+ UBFIZW $0, R1, $1, R2 // 22000053
+
// END
//
// LTYPEE comma
diff --git a/src/cmd/internal/obj/arm64/asm7.go b/src/cmd/internal/obj/arm64/asm7.go
index ff4b1d7..e3bcce8 100644
--- a/src/cmd/internal/obj/arm64/asm7.go
+++ b/src/cmd/internal/obj/arm64/asm7.go
@@ -3264,10 +3264,16 @@
}
switch p.As {
case ABFI:
- o1 = c.opbfm(p, ABFM, 64-r, s-1, rf, rt)
+ if r != 0 {
+ r = 64 - r
+ }
+ o1 = c.opbfm(p, ABFM, r, s-1, rf, rt)
case ABFIW:
- o1 = c.opbfm(p, ABFMW, 32-r, s-1, rf, rt)
+ if r != 0 {
+ r = 32 - r
+ }
+ o1 = c.opbfm(p, ABFMW, r, s-1, rf, rt)
case ABFXIL:
o1 = c.opbfm(p, ABFM, r, r+s-1, rf, rt)
@@ -3276,10 +3282,16 @@
o1 = c.opbfm(p, ABFMW, r, r+s-1, rf, rt)
case ASBFIZ:
- o1 = c.opbfm(p, ASBFM, 64-r, s-1, rf, rt)
+ if r != 0 {
+ r = 64 - r
+ }
+ o1 = c.opbfm(p, ASBFM, r, s-1, rf, rt)
case ASBFIZW:
- o1 = c.opbfm(p, ASBFMW, 32-r, s-1, rf, rt)
+ if r != 0 {
+ r = 32 - r
+ }
+ o1 = c.opbfm(p, ASBFMW, r, s-1, rf, rt)
case ASBFX:
o1 = c.opbfm(p, ASBFM, r, r+s-1, rf, rt)
@@ -3288,10 +3300,16 @@
o1 = c.opbfm(p, ASBFMW, r, r+s-1, rf, rt)
case AUBFIZ:
- o1 = c.opbfm(p, AUBFM, 64-r, s-1, rf, rt)
+ if r != 0 {
+ r = 64 - r
+ }
+ o1 = c.opbfm(p, AUBFM, r, s-1, rf, rt)
case AUBFIZW:
- o1 = c.opbfm(p, AUBFMW, 32-r, s-1, rf, rt)
+ if r != 0 {
+ r = 32 - r
+ }
+ o1 = c.opbfm(p, AUBFMW, r, s-1, rf, rt)
case AUBFX:
o1 = c.opbfm(p, AUBFM, r, r+s-1, rf, rt)
