RISC-V: The vtype immediate with more than the defined 8 bits are preserved.

According the rvv spec,
https://github.com/riscv/riscv-v-spec/blob/master/vtype-format.adoc

The bits of vtype immediate from 8 to (xlen - 1) should be reserved.
Therefore, we should also dump the vtype immediate as numbers, when
they are set over 8-bits.  I think this is a bug that we used to support
vediv extension and use the bit 8 and 9 of vtype, but forgot to update
the behavior when removing the vediv.

Consider the testcases,

vsetvli  a0, a1,  0x700    # the reserved bit 10, 9 and 8 are used.
vsetvli  a0, a1,  0x400    # the reserved bit 10 is used.
vsetvli  a0, a1,  0x300    # the reserved bit 9 and 8 are used.
vsetvli  a0, a1,  0x100    # the reserved bit 8 is used.
vsetivli a0, 0xb, 0x300    # the reserved bit 9 and 8 are used.
vsetivli a0, 0xb, 0x100    # the reserved bit 8 is used.

The original objdump shows the following result,

0000000000000000 <.text>:
   0:   7005f557                vsetvli a0,a1,1792
   4:   4005f557                vsetvli a0,a1,1024
   8:   3005f557                vsetvli a0,a1,e8,m1,tu,mu
   c:   1005f557                vsetvli a0,a1,e8,m1,tu,mu
  10:   f005f557                vsetivli        a0,11,e8,m1,tu,mu
  14:   d005f557                vsetivli        a0,11,e8,m1,tu,mu

But in fact the correct result should be,

0000000000000000 <.text>:
   0:   7005f557                vsetvli a0,a1,1792
   4:   4005f557                vsetvli a0,a1,1024
   8:   3005f557                vsetvli a0,a1,768
   c:   1005f557                vsetvli a0,a1,256
  10:   f005f557                vsetivli        a0,11,768
  14:   d005f557                vsetivli        a0,11,256

gas/
	* testsuite/gas/riscv/vector-insns.d: Added testcases to
	test the reserved bit 8 to (xlen-1) of vtype.
	* testsuite/gas/riscv/vector-insns.s: Likewise.
include/
	* opcode/riscv.h: Removed OP_MASK_VTYPE_RES and OP_SH_VTYPE_RES,
	since they are different for operand Vc and Vb.
opcodes/
	* riscv-dis.c (print_insn_args): Updated imm_vtype_res to
	extract the reserved immediate of vtype correctly.

diff --git a/gas/testsuite/gas/riscv/vector-insns.d b/gas/testsuite/gas/riscv/vector-insns.d
index 6325c7489aaebb8076991d2922b34e9fb8802cd4..71764aa1f347d27509c4b57c79b82bd232272406 100644 (file)
--- a/gas/testsuite/gas/riscv/vector-insns.d
+++ b/gas/testsuite/gas/riscv/vector-insns.d
@@ -24,6 +24,12 @@ Disassembly of section .text:
 [      ]+[0-9a-f]+:[   ]+c4a5f557[     ]+vsetivli[     ]+a0,11,e16,m4,ta,mu
 [      ]+[0-9a-f]+:[   ]+c165f557[     ]+vsetivli[     ]+a0,11,e32,mf4,tu,mu
 [      ]+[0-9a-f]+:[   ]+c9d5f557[     ]+vsetivli[     ]+a0,11,e64,mf8,tu,ma
+[      ]+[0-9a-f]+:[   ]+7005f557[     ]+vsetvli[      ]+a0,a1,1792
+[      ]+[0-9a-f]+:[   ]+4005f557[     ]+vsetvli[      ]+a0,a1,1024
+[      ]+[0-9a-f]+:[   ]+3005f557[     ]+vsetvli[      ]+a0,a1,768
+[      ]+[0-9a-f]+:[   ]+1005f557[     ]+vsetvli[      ]+a0,a1,256
+[      ]+[0-9a-f]+:[   ]+f005f557[     ]+vsetivli[     ]+a0,11,768
+[      ]+[0-9a-f]+:[   ]+d005f557[     ]+vsetivli[     ]+a0,11,256
 [      ]+[0-9a-f]+:[   ]+02b50207[     ]+vlm.v[        ]+v4,\(a0\)
 [      ]+[0-9a-f]+:[   ]+02b50207[     ]+vlm.v[        ]+v4,\(a0\)
 [      ]+[0-9a-f]+:[   ]+02b50207[     ]+vlm.v[        ]+v4,\(a0\)

diff --git a/gas/testsuite/gas/riscv/vector-insns.s b/gas/testsuite/gas/riscv/vector-insns.s
index 837026443fb540275ddd2b70acb79e71f26056d0..a4b98d810268f41fd7dbdd69304346d930cfab5e 100644 (file)
--- a/gas/testsuite/gas/riscv/vector-insns.s
+++ b/gas/testsuite/gas/riscv/vector-insns.s
@@ -16,6 +16,13 @@
        vsetivli a0, 0xb, e32, mf4, mu
        vsetivli a0, 0xb, e64, mf8, tu, ma
 
+       vsetvli  a0, a1,  0x700
+       vsetvli  a0, a1,  0x400
+       vsetvli  a0, a1,  0x300
+       vsetvli  a0, a1,  0x100
+       vsetivli a0, 0xb, 0x300
+       vsetivli a0, 0xb, 0x100
+
        vlm.v v4, (a0)
        vlm.v v4, 0(a0)
        vle1.v v4, (a0)         # Alias of vlm.v

diff --git a/include/opcode/riscv.h b/include/opcode/riscv.h
index 8cb4fd237566f072f8bb7b47f6db071da6fd113e..14889972abcee2e0d0801f6c4c0c7346fabc9cd1 100644 (file)
--- a/include/opcode/riscv.h
+++ b/include/opcode/riscv.h
@@ -306,8 +306,6 @@ static const char * const riscv_pred_succ[16] =
 #define OP_SH_VTA              6
 #define OP_MASK_VMA            0x1
 #define OP_SH_VMA              7
-#define OP_MASK_VTYPE_RES      0x1
-#define OP_SH_VTYPE_RES                10
 #define OP_MASK_VWD            0x1
 #define OP_SH_VWD              26
 

diff --git a/opcodes/riscv-dis.c b/opcodes/riscv-dis.c
index a3c85067530950876b4a8537f21640ca5526be0e..d646dd56e64d50e96d45c4f68204fcd9d3e5fbc4 100644 (file)
--- a/opcodes/riscv-dis.c
+++ b/opcodes/riscv-dis.c
@@ -328,7 +328,7 @@ print_insn_args (const char *oparg, insn_t l, bfd_vma pc, disassemble_info *info
                unsigned int imm_vsew = EXTRACT_OPERAND (VSEW, imm);
                unsigned int imm_vta = EXTRACT_OPERAND (VTA, imm);
                unsigned int imm_vma = EXTRACT_OPERAND (VMA, imm);
-               unsigned int imm_vtype_res = EXTRACT_OPERAND (VTYPE_RES, imm);
+               unsigned int imm_vtype_res = (imm >> 8);
 
                if (imm_vsew < ARRAY_SIZE (riscv_vsew)
                    && imm_vlmul < ARRAY_SIZE (riscv_vlmul)