[PATCH v2 07/13] x86/kvm/emulate: Introduce COP1SRC2

Peter Zijlstra
2025-04-30T11:26:46Z

Replace the FASTOP1SRC2*() instructions.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
arch/x86/kvm/emulate.c | 34 ++++++++++++++++++++++++++--------
1 file changed, 26 insertions(+), 8 deletions(-)

--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -317,6 +317,24 @@ static int em_##op(struct x86_emulate_ct
ON64(case 8: COP_ASM1(op##q, rax); break;) \
COP_END

+/* 1-operand, using "c" (src2) */
+#define COP1SRC2(op, name) \
+ COP_START(name) \
+ case 1: COP_ASM1(op##b, cl); break; \
+ case 2: COP_ASM1(op##w, cx); break; \
+ case 4: COP_ASM1(op##l, ecx); break; \
+ ON64(case 8: COP_ASM1(op##q, rcx); break;) \
+ COP_END
+
+/* 1-operand, using "c" (src2) with exception */
+#define COP1SRC2EX(op, name) \
+ COP_START(name) \
+ case 1: COP_ASM1_EX(op##b, cl); break; \
+ case 2: COP_ASM1_EX(op##w, cx); break; \
+ case 4: COP_ASM1_EX(op##l, ecx); break; \
+ ON64(case 8: COP_ASM1(op##q, rcx); break;) \
+ COP_END
+
/* 2-operand, using "a" (dst), "d" (src) */
#define COP2(op) \
COP_START(op) \
@@ -1074,10 +1092,10 @@ COP2(cmp);
COP2(test);
COP2(xadd);

-FASTOP1SRC2(mul, mul_ex);
-FASTOP1SRC2(imul, imul_ex);
-FASTOP1SRC2EX(div, div_ex);
-FASTOP1SRC2EX(idiv, idiv_ex);
+COP1SRC2(mul, mul_ex);
+COP1SRC2(imul, imul_ex);
+COP1SRC2EX(div, div_ex);
+COP1SRC2EX(idiv, idiv_ex);

FASTOP3WCL(shld);
FASTOP3WCL(shrd);
@@ -4103,10 +4121,10 @@ static const struct opcode group3[] = {
I(DstMem | SrcImm | NoWrite, em_test),
I(DstMem | SrcNone | Lock, em_not),
I(DstMem | SrcNone | Lock, em_neg),
- F(DstXacc | Src2Mem, em_mul_ex),
- F(DstXacc | Src2Mem, em_imul_ex),
- F(DstXacc | Src2Mem, em_div_ex),
- F(DstXacc | Src2Mem, em_idiv_ex),
+ I(DstXacc | Src2Mem, em_mul_ex),
+ I(DstXacc | Src2Mem, em_imul_ex),
+ I(DstXacc | Src2Mem, em_div_ex),
+ I(DstXacc | Src2Mem, em_idiv_ex),
};

static const struct opcode group4[] = {