target/ppc: Implement xxm[tf]acc and xxsetaccz

Implement the following PowerISA v3.1 instructions:
xxmfacc: VSX Move From Accumulator
xxmtacc: VSX Move To Accumulator
xxsetaccz: VSX Set Accumulator to Zero

The PowerISA 3.1 mentions that for the current version of the
architecture, "the hardware implementation provides the effect of ACC[i]
and VSRs 4*i to 4*i + 3 logically containing the same data" and "The
Accumulators introduce no new logical state at this time" (page 501).
For now it seems unnecessary to create new structures, so this patch
just uses ACC[i] as VSRs 4*i to 4*i+3 and therefore move to and from
accumulators are no-ops.

Signed-off-by: Lucas Mateus Castro (alqotel) <lucas.araujo@eldorado.org.br>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220524140537.27451-2-lucas.araujo@eldorado.org.br>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>

diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h
index bf8f8aad2c24f3a593aa131315d6f0a28a0539e8..c8652068274ef3083b7ed215d10f2fb16525812f 100644 (file)
--- a/target/ppc/cpu.h
+++ b/target/ppc/cpu.h
@@ -2663,6 +2663,11 @@ static inline int vsr_full_offset(int i)
     return offsetof(CPUPPCState, vsr[i].u64[0]);
 }
 
+static inline int acc_full_offset(int i)
+{
+    return vsr_full_offset(i * 4);
+}
+
 static inline int fpr_offset(int i)
 {
     return vsr64_offset(i, true);

diff --git a/target/ppc/insn32.decode b/target/ppc/insn32.decode
index f001c02a8c1e951ac86ce49e16d75bea2bd3b11a..c0f545ca383d80855f96c00cfc3e0fffc4ff485a 100644 (file)
--- a/target/ppc/insn32.decode
+++ b/target/ppc/insn32.decode
@@ -154,6 +154,9 @@
 &X_vrt_frbp     vrt frbp
 @X_vrt_frbp     ...... vrt:5 ..... ....0 .......... .           &X_vrt_frbp frbp=%x_frbp
 
+&X_a            ra
+@X_a            ...... ra:3 .. ..... ..... .......... .         &X_a
+
 %xx_xt          0:1 21:5
 %xx_xb          1:1 11:5
 %xx_xa          2:1 16:5
@@ -734,3 +737,9 @@ XVTLSBB         111100 ... -- 00010 ..... 111011011 . - @XX2_bf_xb
 &XL_s           s:uint8_t
 @XL_s           ......-------------- s:1 .......... -   &XL_s
 RFEBB           010011-------------- .   0010010010 -   @XL_s
+
+## Accumulator Instructions
+
+XXMFACC         011111 ... -- 00000 ----- 0010110001 -   @X_a
+XXMTACC         011111 ... -- 00001 ----- 0010110001 -   @X_a
+XXSETACCZ       011111 ... -- 00011 ----- 0010110001 -   @X_a

diff --git a/target/ppc/translate/vsx-impl.c.inc b/target/ppc/translate/vsx-impl.c.inc
index 900c1a1ab2311def9466fbaa522e79979c4008b0..235be360e2b42b68198ffd420c4ae319ad957dcb 100644 (file)
--- a/target/ppc/translate/vsx-impl.c.inc
+++ b/target/ppc/translate/vsx-impl.c.inc
@@ -2816,6 +2816,37 @@ static bool trans_XVCVBF16SPN(DisasContext *ctx, arg_XX2 *a)
     return true;
 }
 
+    /*
+     *  The PowerISA 3.1 mentions that for the current version of the
+     *  architecture, "the hardware implementation provides the effect of
+     *  ACC[i] and VSRs 4*i to 4*i + 3 logically containing the same data"
+     *  and "The Accumulators introduce no new logical state at this time"
+     *  (page 501). For now it seems unnecessary to create new structures,
+     *  so ACC[i] is the same as VSRs 4*i to 4*i+3 and therefore
+     *  move to and from accumulators are no-ops.
+     */
+static bool trans_XXMFACC(DisasContext *ctx, arg_X_a *a)
+{
+    REQUIRE_INSNS_FLAGS2(ctx, ISA310);
+    REQUIRE_VSX(ctx);
+    return true;
+}
+
+static bool trans_XXMTACC(DisasContext *ctx, arg_X_a *a)
+{
+    REQUIRE_INSNS_FLAGS2(ctx, ISA310);
+    REQUIRE_VSX(ctx);
+    return true;
+}
+
+static bool trans_XXSETACCZ(DisasContext *ctx, arg_X_a *a)
+{
+    REQUIRE_INSNS_FLAGS2(ctx, ISA310);
+    REQUIRE_VSX(ctx);
+    tcg_gen_gvec_dup_imm(MO_64, acc_full_offset(a->ra), 64, 64, 0);
+    return true;
+}
+
 #undef GEN_XX2FORM
 #undef GEN_XX3FORM
 #undef GEN_XX2IFORM