qemu-e2k/target/i386/tcg/decode-new.h
Paolo Bonzini 2872b0f390 target/i386: implement FMA instructions
The only issue with FMA instructions is that there are _a lot_ of them (30
opcodes, each of which comes in up to 4 versions depending on VEX.W and
VEX.L; a total of 96 possibilities).  However, they can be implement with
only 6 helpers, two for scalar operations and four for packed operations.
(Scalar versions do not do any merging; they only affect the bottom 32
or 64 bits of the output operand.  Therefore, there is no separate XMM
and YMM of the scalar helpers).

First, we can reduce the number of helpers to one third by passing four
operands (one output and three inputs); the reordering of which operands
go to the multiply and which go to the add is done in emit.c.

Second, the different instructions also dispatch to the same softfloat
function, so the flags for float32_muladd and float64_muladd are passed
in the helper as int arguments, with a little extra complication to
handle FMADDSUB and FMSUBADD.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-10-22 09:05:54 +02:00

253 lines
7.8 KiB
C

/*
* Decode table flags, mostly based on Intel SDM.
*
* Copyright (c) 2022 Red Hat, Inc.
*
* Author: Paolo Bonzini <pbonzini@redhat.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
typedef enum X86OpType {
X86_TYPE_None,
X86_TYPE_A, /* Implicit */
X86_TYPE_B, /* VEX.vvvv selects a GPR */
X86_TYPE_C, /* REG in the modrm byte selects a control register */
X86_TYPE_D, /* REG in the modrm byte selects a debug register */
X86_TYPE_E, /* ALU modrm operand */
X86_TYPE_F, /* EFLAGS/RFLAGS */
X86_TYPE_G, /* REG in the modrm byte selects a GPR */
X86_TYPE_H, /* For AVX, VEX.vvvv selects an XMM/YMM register */
X86_TYPE_I, /* Immediate */
X86_TYPE_J, /* Relative offset for a jump */
X86_TYPE_L, /* The upper 4 bits of the immediate select a 128-bit register */
X86_TYPE_M, /* modrm byte selects a memory operand */
X86_TYPE_N, /* R/M in the modrm byte selects an MMX register */
X86_TYPE_O, /* Absolute address encoded in the instruction */
X86_TYPE_P, /* reg in the modrm byte selects an MMX register */
X86_TYPE_Q, /* MMX modrm operand */
X86_TYPE_R, /* R/M in the modrm byte selects a register */
X86_TYPE_S, /* reg selects a segment register */
X86_TYPE_U, /* R/M in the modrm byte selects an XMM/YMM register */
X86_TYPE_V, /* reg in the modrm byte selects an XMM/YMM register */
X86_TYPE_W, /* XMM/YMM modrm operand */
X86_TYPE_X, /* string source */
X86_TYPE_Y, /* string destination */
/* Custom */
X86_TYPE_WM, /* modrm byte selects an XMM/YMM memory operand */
X86_TYPE_2op, /* 2-operand RMW instruction */
X86_TYPE_LoBits, /* encoded in bits 0-2 of the operand + REX.B */
X86_TYPE_0, /* Hard-coded GPRs (RAX..RDI) */
X86_TYPE_1,
X86_TYPE_2,
X86_TYPE_3,
X86_TYPE_4,
X86_TYPE_5,
X86_TYPE_6,
X86_TYPE_7,
X86_TYPE_ES, /* Hard-coded segment registers */
X86_TYPE_CS,
X86_TYPE_SS,
X86_TYPE_DS,
X86_TYPE_FS,
X86_TYPE_GS,
} X86OpType;
typedef enum X86OpSize {
X86_SIZE_None,
X86_SIZE_a, /* BOUND operand */
X86_SIZE_b, /* byte */
X86_SIZE_d, /* 32-bit */
X86_SIZE_dq, /* SSE/AVX 128-bit */
X86_SIZE_p, /* Far pointer */
X86_SIZE_pd, /* SSE/AVX packed double precision */
X86_SIZE_pi, /* MMX */
X86_SIZE_ps, /* SSE/AVX packed single precision */
X86_SIZE_q, /* 64-bit */
X86_SIZE_qq, /* AVX 256-bit */
X86_SIZE_s, /* Descriptor */
X86_SIZE_sd, /* SSE/AVX scalar double precision */
X86_SIZE_ss, /* SSE/AVX scalar single precision */
X86_SIZE_si, /* 32-bit GPR */
X86_SIZE_v, /* 16/32/64-bit, based on operand size */
X86_SIZE_w, /* 16-bit */
X86_SIZE_x, /* 128/256-bit, based on operand size */
X86_SIZE_y, /* 32/64-bit, based on operand size */
X86_SIZE_z, /* 16-bit for 16-bit operand size, else 32-bit */
/* Custom */
X86_SIZE_d64,
X86_SIZE_f64,
X86_SIZE_ph, /* SSE/AVX packed half precision */
} X86OpSize;
typedef enum X86CPUIDFeature {
X86_FEAT_None,
X86_FEAT_3DNOW,
X86_FEAT_ADX,
X86_FEAT_AES,
X86_FEAT_AVX,
X86_FEAT_AVX2,
X86_FEAT_BMI1,
X86_FEAT_BMI2,
X86_FEAT_F16C,
X86_FEAT_FMA,
X86_FEAT_MOVBE,
X86_FEAT_PCLMULQDQ,
X86_FEAT_SSE,
X86_FEAT_SSE2,
X86_FEAT_SSE3,
X86_FEAT_SSSE3,
X86_FEAT_SSE41,
X86_FEAT_SSE42,
X86_FEAT_SSE4A,
} X86CPUIDFeature;
/* Execution flags */
typedef enum X86OpUnit {
X86_OP_SKIP, /* not valid or managed by emission function */
X86_OP_SEG, /* segment selector */
X86_OP_CR, /* control register */
X86_OP_DR, /* debug register */
X86_OP_INT, /* loaded into/stored from s->T0/T1 */
X86_OP_IMM, /* immediate */
X86_OP_SSE, /* address in either s->ptrX or s->A0 depending on has_ea */
X86_OP_MMX, /* address in either s->ptrX or s->A0 depending on has_ea */
} X86OpUnit;
typedef enum X86InsnSpecial {
X86_SPECIAL_None,
/* Always locked if it has a memory operand (XCHG) */
X86_SPECIAL_Locked,
/* Fault outside protected mode */
X86_SPECIAL_ProtMode,
/*
* Register operand 0/2 is zero extended to 32 bits. Rd/Mb or Rd/Mw
* in the manual.
*/
X86_SPECIAL_ZExtOp0,
X86_SPECIAL_ZExtOp2,
/*
* Register operand 2 is extended to full width, while a memory operand
* is doubled in size if VEX.L=1.
*/
X86_SPECIAL_AVXExtMov,
/*
* MMX instruction exists with no prefix; if there is no prefix, V/H/W/U operands
* become P/P/Q/N, and size "x" becomes "q".
*/
X86_SPECIAL_MMX,
/* Illegal or exclusive to 64-bit mode */
X86_SPECIAL_i64,
X86_SPECIAL_o64,
} X86InsnSpecial;
/*
* Special cases for instructions that operate on XMM/YMM registers. Intel
* retconned all of them to have VEX exception classes other than 0 and 13, so
* all these only matter for instructions that have a VEX exception class.
* Based on tables in the "AVX and SSE Instruction Exception Specification"
* section of the manual.
*/
typedef enum X86VEXSpecial {
/* Legacy SSE instructions that allow unaligned operands */
X86_VEX_SSEUnaligned,
/*
* Used for instructions that distinguish the XMM operand type with an
* instruction prefix; legacy SSE encodings will allow unaligned operands
* for scalar operands only (identified by a REP prefix). In this case,
* the decoding table uses "x" for the vector operands instead of specifying
* pd/ps/sd/ss individually.
*/
X86_VEX_REPScalar,
/*
* VEX instructions that only support 256-bit operands with AVX2 (Table 2-17
* column 3). Columns 2 and 4 (instructions limited to 256- and 127-bit
* operands respectively) are implicit in the presence of dq and qq
* operands, and thus handled by decode_op_size.
*/
X86_VEX_AVX2_256,
} X86VEXSpecial;
typedef struct X86OpEntry X86OpEntry;
typedef struct X86DecodedInsn X86DecodedInsn;
/* Decode function for multibyte opcodes. */
typedef void (*X86DecodeFunc)(DisasContext *s, CPUX86State *env, X86OpEntry *entry, uint8_t *b);
/* Code generation function. */
typedef void (*X86GenFunc)(DisasContext *s, CPUX86State *env, X86DecodedInsn *decode);
struct X86OpEntry {
/* Based on the is_decode flags. */
union {
X86GenFunc gen;
X86DecodeFunc decode;
};
/* op0 is always written, op1 and op2 are always read. */
X86OpType op0:8;
X86OpSize s0:8;
X86OpType op1:8;
X86OpSize s1:8;
X86OpType op2:8;
X86OpSize s2:8;
/* Must be I and b respectively if present. */
X86OpType op3:8;
X86OpSize s3:8;
X86InsnSpecial special:8;
X86CPUIDFeature cpuid:8;
unsigned vex_class:8;
X86VEXSpecial vex_special:8;
uint16_t valid_prefix:16;
bool is_decode:1;
};
typedef struct X86DecodedOp {
int8_t n;
MemOp ot; /* For b/c/d/p/s/q/v/w/y/z */
X86OpUnit unit;
bool has_ea;
int offset; /* For MMX and SSE */
/*
* This field is used internally by macros OP0_PTR/OP1_PTR/OP2_PTR,
* do not access directly!
*/
TCGv_ptr v_ptr;
} X86DecodedOp;
struct X86DecodedInsn {
X86OpEntry e;
X86DecodedOp op[3];
target_ulong immediate;
AddressParts mem;
uint8_t b;
};