* [Qemu-devel] [PATCH v6 2/3] tcg: Add extended GETPC mechanism for MMU helpers with ldst optimization
2012-10-16 7:23 [Qemu-devel] [PATCH v6 0/3] tcg: enhance code generation quality for qemu_ld/st IRs Yeongkyoon Lee
2012-10-16 7:23 ` [Qemu-devel] [PATCH v6 1/3] configure: Add CONFIG_QEMU_LDST_OPTIMIZATION for TCG qemu_ld/st optimization Yeongkyoon Lee
@ 2012-10-16 7:23 ` Yeongkyoon Lee
2012-10-16 7:23 ` [Qemu-devel] [PATCH v6 3/3] tcg: Optimize qemu_ld/st by generating slow paths at the end of a block Yeongkyoon Lee
2 siblings, 0 replies; 6+ messages in thread
From: Yeongkyoon Lee @ 2012-10-16 7:23 UTC (permalink / raw)
To: qemu-devel; +Cc: blauwirbel, Yeongkyoon Lee, aurelien, rth
Add GETPC_EXT which is used by MMU helpers to selectively calculate the code
address of accessing guest memory when called from a qemu_ld/st optimized code
or a C function. Currently, it supports only i386 and x86-64 hosts.
Signed-off-by: Yeongkyoon Lee <yeongkyoon.lee@samsung.com>
---
exec-all.h | 36 ++++++++++++++++++++++++++++++++++++
exec.c | 11 +++++++++++
softmmu_template.h | 16 ++++++++--------
3 files changed, 55 insertions(+), 8 deletions(-)
diff --git a/exec-all.h b/exec-all.h
index 6516da0..9eda604 100644
--- a/exec-all.h
+++ b/exec-all.h
@@ -311,6 +311,42 @@ extern uintptr_t tci_tb_ptr;
# define GETPC() ((uintptr_t)__builtin_return_address(0) - 1)
#endif
+#if defined(CONFIG_QEMU_LDST_OPTIMIZATION) && defined(CONFIG_SOFTMMU)
+/* qemu_ld/st optimization split code generation to fast and slow path, thus,
+ it needs special handling for an MMU helper which is called from the slow
+ path, to get the fast path's pc without any additional argument.
+ It uses a tricky solution which embeds the fast path pc into the slow path.
+
+ Code flow in slow path:
+ (1) pre-process
+ (2) call MMU helper
+ (3) jump to (5)
+ (4) fast path information (implementation specific)
+ (5) post-process (e.g. stack adjust)
+ (6) jump to corresponding code of the next of fast path
+ */
+# if defined(__i386__) || defined(__x86_64__)
+/* To avoid broken disassembling, long jmp is used for embedding fast path pc,
+ so that the destination is the next code of fast path, though this jmp is
+ never executed.
+
+ call MMU helper
+ jmp POST_PROC (2byte) <- GETRA()
+ jmp NEXT_CODE (5byte)
+ POST_PROCESS ... <- GETRA() + 7
+ */
+# define GETRA() ((uintptr_t)__builtin_return_address(0))
+# define GETPC_LDST() ((uintptr_t)(GETRA() + 7 + \
+ *(int32_t *)((void *)GETRA() + 3) - 1))
+# else
+# error "CONFIG_QEMU_LDST_OPTIMIZATION needs GETPC_LDST() implementation!"
+# endif
+bool is_tcg_gen_code(uintptr_t pc_ptr);
+# define GETPC_EXT() (is_tcg_gen_code(GETRA()) ? GETPC_LDST() : GETPC())
+#else
+# define GETPC_EXT() GETPC()
+#endif
+
#if !defined(CONFIG_USER_ONLY)
struct MemoryRegion *iotlb_to_region(target_phys_addr_t index);
diff --git a/exec.c b/exec.c
index 7899042..8a825a9 100644
--- a/exec.c
+++ b/exec.c
@@ -1379,6 +1379,17 @@ void tb_link_page(TranslationBlock *tb,
mmap_unlock();
}
+#if defined(CONFIG_QEMU_LDST_OPTIMIZATION) && defined(CONFIG_SOFTMMU)
+/* check whether the give addr is in TCG generated code buffer or not */
+bool is_tcg_gen_code(uintptr_t tc_ptr)
+{
+ /* This can be called during code generation, code_gen_buffer_max_size
+ is used instead of code_gen_ptr for upper boundary checking */
+ return (tc_ptr >= (uintptr_t)code_gen_buffer &&
+ tc_ptr < (uintptr_t)(code_gen_buffer + code_gen_buffer_max_size));
+}
+#endif
+
/* find the TB 'tb' such that tb[0].tc_ptr <= tc_ptr <
tb[1].tc_ptr. Return NULL if not found */
TranslationBlock *tb_find_pc(uintptr_t tc_ptr)
diff --git a/softmmu_template.h b/softmmu_template.h
index e2490f0..d23de8c 100644
--- a/softmmu_template.h
+++ b/softmmu_template.h
@@ -111,13 +111,13 @@ glue(glue(helper_ld, SUFFIX), MMUSUFFIX)(CPUArchState *env, target_ulong addr,
/* IO access */
if ((addr & (DATA_SIZE - 1)) != 0)
goto do_unaligned_access;
- retaddr = GETPC();
+ retaddr = GETPC_EXT();
ioaddr = env->iotlb[mmu_idx][index];
res = glue(io_read, SUFFIX)(env, ioaddr, addr, retaddr);
} else if (((addr & ~TARGET_PAGE_MASK) + DATA_SIZE - 1) >= TARGET_PAGE_SIZE) {
/* slow unaligned access (it spans two pages or IO) */
do_unaligned_access:
- retaddr = GETPC();
+ retaddr = GETPC_EXT();
#ifdef ALIGNED_ONLY
do_unaligned_access(env, addr, READ_ACCESS_TYPE, mmu_idx, retaddr);
#endif
@@ -128,7 +128,7 @@ glue(glue(helper_ld, SUFFIX), MMUSUFFIX)(CPUArchState *env, target_ulong addr,
uintptr_t addend;
#ifdef ALIGNED_ONLY
if ((addr & (DATA_SIZE - 1)) != 0) {
- retaddr = GETPC();
+ retaddr = GETPC_EXT();
do_unaligned_access(env, addr, READ_ACCESS_TYPE, mmu_idx, retaddr);
}
#endif
@@ -138,7 +138,7 @@ glue(glue(helper_ld, SUFFIX), MMUSUFFIX)(CPUArchState *env, target_ulong addr,
}
} else {
/* the page is not in the TLB : fill it */
- retaddr = GETPC();
+ retaddr = GETPC_EXT();
#ifdef ALIGNED_ONLY
if ((addr & (DATA_SIZE - 1)) != 0)
do_unaligned_access(env, addr, READ_ACCESS_TYPE, mmu_idx, retaddr);
@@ -257,12 +257,12 @@ void glue(glue(helper_st, SUFFIX), MMUSUFFIX)(CPUArchState *env,
/* IO access */
if ((addr & (DATA_SIZE - 1)) != 0)
goto do_unaligned_access;
- retaddr = GETPC();
+ retaddr = GETPC_EXT();
ioaddr = env->iotlb[mmu_idx][index];
glue(io_write, SUFFIX)(env, ioaddr, val, addr, retaddr);
} else if (((addr & ~TARGET_PAGE_MASK) + DATA_SIZE - 1) >= TARGET_PAGE_SIZE) {
do_unaligned_access:
- retaddr = GETPC();
+ retaddr = GETPC_EXT();
#ifdef ALIGNED_ONLY
do_unaligned_access(env, addr, 1, mmu_idx, retaddr);
#endif
@@ -273,7 +273,7 @@ void glue(glue(helper_st, SUFFIX), MMUSUFFIX)(CPUArchState *env,
uintptr_t addend;
#ifdef ALIGNED_ONLY
if ((addr & (DATA_SIZE - 1)) != 0) {
- retaddr = GETPC();
+ retaddr = GETPC_EXT();
do_unaligned_access(env, addr, 1, mmu_idx, retaddr);
}
#endif
@@ -283,7 +283,7 @@ void glue(glue(helper_st, SUFFIX), MMUSUFFIX)(CPUArchState *env,
}
} else {
/* the page is not in the TLB : fill it */
- retaddr = GETPC();
+ retaddr = GETPC_EXT();
#ifdef ALIGNED_ONLY
if ((addr & (DATA_SIZE - 1)) != 0)
do_unaligned_access(env, addr, 1, mmu_idx, retaddr);
--
1.7.5.4
^ permalink raw reply related [flat|nested] 6+ messages in thread* [Qemu-devel] [PATCH v6 3/3] tcg: Optimize qemu_ld/st by generating slow paths at the end of a block
2012-10-16 7:23 [Qemu-devel] [PATCH v6 0/3] tcg: enhance code generation quality for qemu_ld/st IRs Yeongkyoon Lee
2012-10-16 7:23 ` [Qemu-devel] [PATCH v6 1/3] configure: Add CONFIG_QEMU_LDST_OPTIMIZATION for TCG qemu_ld/st optimization Yeongkyoon Lee
2012-10-16 7:23 ` [Qemu-devel] [PATCH v6 2/3] tcg: Add extended GETPC mechanism for MMU helpers with ldst optimization Yeongkyoon Lee
@ 2012-10-16 7:23 ` Yeongkyoon Lee
2012-10-17 23:44 ` Richard Henderson
2 siblings, 1 reply; 6+ messages in thread
From: Yeongkyoon Lee @ 2012-10-16 7:23 UTC (permalink / raw)
To: qemu-devel; +Cc: blauwirbel, Yeongkyoon Lee, aurelien, rth
Add optimized TCG qemu_ld/st generation which locates the code of TLB miss
cases at the end of a block after generating the other IRs.
Currently, this optimization supports only i386 and x86_64 hosts.
Signed-off-by: Yeongkyoon Lee <yeongkyoon.lee@samsung.com>
---
tcg/i386/tcg-target.c | 415 +++++++++++++++++++++++++++++++++----------------
tcg/tcg.c | 12 ++
tcg/tcg.h | 30 ++++
3 files changed, 324 insertions(+), 133 deletions(-)
diff --git a/tcg/i386/tcg-target.c b/tcg/i386/tcg-target.c
index 4952c05..51abe85 100644
--- a/tcg/i386/tcg-target.c
+++ b/tcg/i386/tcg-target.c
@@ -1001,6 +1001,17 @@ static const void *qemu_st_helpers[4] = {
helper_stq_mmu,
};
+static void add_qemu_ldst_label(TCGContext *s,
+ int is_ld,
+ int opc,
+ int data_reg,
+ int data_reg2,
+ int addrlo_reg,
+ int addrhi_reg,
+ int mem_index,
+ uint8_t *raddr,
+ uint8_t **label_ptr);
+
/* Perform the TLB load and compare.
Inputs:
@@ -1059,19 +1070,19 @@ static inline void tcg_out_tlb_load(TCGContext *s, int addrlo_idx,
tcg_out_mov(s, type, r0, addrlo);
- /* jne label1 */
- tcg_out8(s, OPC_JCC_short + JCC_JNE);
+ /* jne slow_path */
+ tcg_out_opc(s, OPC_JCC_long + JCC_JNE, 0, 0, 0);
label_ptr[0] = s->code_ptr;
- s->code_ptr++;
+ s->code_ptr += 4;
if (TARGET_LONG_BITS > TCG_TARGET_REG_BITS) {
/* cmp 4(r1), addrhi */
tcg_out_modrm_offset(s, OPC_CMP_GvEv, args[addrlo_idx+1], r1, 4);
- /* jne label1 */
- tcg_out8(s, OPC_JCC_short + JCC_JNE);
+ /* jne slow_path */
+ tcg_out_opc(s, OPC_JCC_long + JCC_JNE, 0, 0, 0);
label_ptr[1] = s->code_ptr;
- s->code_ptr++;
+ s->code_ptr += 4;
}
/* TLB Hit. */
@@ -1169,12 +1180,7 @@ static void tcg_out_qemu_ld(TCGContext *s, const TCGArg *args,
int addrlo_idx;
#if defined(CONFIG_SOFTMMU)
int mem_index, s_bits;
-#if TCG_TARGET_REG_BITS == 64
- int arg_idx;
-#else
- int stack_adjust;
-#endif
- uint8_t *label_ptr[3];
+ uint8_t *label_ptr[2];
#endif
data_reg = args[0];
@@ -1194,93 +1200,17 @@ static void tcg_out_qemu_ld(TCGContext *s, const TCGArg *args,
/* TLB Hit. */
tcg_out_qemu_ld_direct(s, data_reg, data_reg2, TCG_REG_L0, 0, opc);
- /* jmp label2 */
- tcg_out8(s, OPC_JMP_short);
- label_ptr[2] = s->code_ptr;
- s->code_ptr++;
-
- /* TLB Miss. */
-
- /* label1: */
- *label_ptr[0] = s->code_ptr - label_ptr[0] - 1;
- if (TARGET_LONG_BITS > TCG_TARGET_REG_BITS) {
- *label_ptr[1] = s->code_ptr - label_ptr[1] - 1;
- }
-
- /* XXX: move that code at the end of the TB */
-#if TCG_TARGET_REG_BITS == 32
- tcg_out_pushi(s, mem_index);
- stack_adjust = 4;
- if (TARGET_LONG_BITS == 64) {
- tcg_out_push(s, args[addrlo_idx + 1]);
- stack_adjust += 4;
- }
- tcg_out_push(s, args[addrlo_idx]);
- stack_adjust += 4;
- tcg_out_push(s, TCG_AREG0);
- stack_adjust += 4;
-#else
- /* The first argument is already loaded with addrlo. */
- arg_idx = 1;
- tcg_out_movi(s, TCG_TYPE_I32, tcg_target_call_iarg_regs[arg_idx],
- mem_index);
- /* XXX/FIXME: suboptimal */
- tcg_out_mov(s, TCG_TYPE_I64, tcg_target_call_iarg_regs[3], TCG_REG_L2);
- tcg_out_mov(s, TCG_TYPE_I64, tcg_target_call_iarg_regs[2], TCG_REG_L1);
- tcg_out_mov(s, TCG_TYPE_I64, tcg_target_call_iarg_regs[1], TCG_REG_L0);
- tcg_out_mov(s, TCG_TYPE_I64, tcg_target_call_iarg_regs[0], TCG_AREG0);
-#endif
-
- tcg_out_calli(s, (tcg_target_long)qemu_ld_helpers[s_bits]);
-
-#if TCG_TARGET_REG_BITS == 32
- if (stack_adjust == (TCG_TARGET_REG_BITS / 8)) {
- /* Pop and discard. This is 2 bytes smaller than the add. */
- tcg_out_pop(s, TCG_REG_ECX);
- } else if (stack_adjust != 0) {
- tcg_out_addi(s, TCG_REG_CALL_STACK, stack_adjust);
- }
-#endif
-
- switch(opc) {
- case 0 | 4:
- tcg_out_ext8s(s, data_reg, TCG_REG_EAX, P_REXW);
- break;
- case 1 | 4:
- tcg_out_ext16s(s, data_reg, TCG_REG_EAX, P_REXW);
- break;
- case 0:
- tcg_out_ext8u(s, data_reg, TCG_REG_EAX);
- break;
- case 1:
- tcg_out_ext16u(s, data_reg, TCG_REG_EAX);
- break;
- case 2:
- tcg_out_mov(s, TCG_TYPE_I32, data_reg, TCG_REG_EAX);
- break;
-#if TCG_TARGET_REG_BITS == 64
- case 2 | 4:
- tcg_out_ext32s(s, data_reg, TCG_REG_EAX);
- break;
-#endif
- case 3:
- if (TCG_TARGET_REG_BITS == 64) {
- tcg_out_mov(s, TCG_TYPE_I64, data_reg, TCG_REG_RAX);
- } else if (data_reg == TCG_REG_EDX) {
- /* xchg %edx, %eax */
- tcg_out_opc(s, OPC_XCHG_ax_r32 + TCG_REG_EDX, 0, 0, 0);
- tcg_out_mov(s, TCG_TYPE_I32, data_reg2, TCG_REG_EAX);
- } else {
- tcg_out_mov(s, TCG_TYPE_I32, data_reg, TCG_REG_EAX);
- tcg_out_mov(s, TCG_TYPE_I32, data_reg2, TCG_REG_EDX);
- }
- break;
- default:
- tcg_abort();
- }
-
- /* label2: */
- *label_ptr[2] = s->code_ptr - label_ptr[2] - 1;
+ /* Record the current context of a load into ldst label */
+ add_qemu_ldst_label(s,
+ 1,
+ opc,
+ data_reg,
+ data_reg2,
+ args[addrlo_idx],
+ args[addrlo_idx + 1],
+ mem_index,
+ s->code_ptr,
+ label_ptr);
#else
{
int32_t offset = GUEST_BASE;
@@ -1372,8 +1302,7 @@ static void tcg_out_qemu_st(TCGContext *s, const TCGArg *args,
int addrlo_idx;
#if defined(CONFIG_SOFTMMU)
int mem_index, s_bits;
- int stack_adjust;
- uint8_t *label_ptr[3];
+ uint8_t *label_ptr[2];
#endif
data_reg = args[0];
@@ -1393,20 +1322,225 @@ static void tcg_out_qemu_st(TCGContext *s, const TCGArg *args,
/* TLB Hit. */
tcg_out_qemu_st_direct(s, data_reg, data_reg2, TCG_REG_L0, 0, opc);
- /* jmp label2 */
+ /* Record the current context of a store into ldst label */
+ add_qemu_ldst_label(s,
+ 0,
+ opc,
+ data_reg,
+ data_reg2,
+ args[addrlo_idx],
+ args[addrlo_idx + 1],
+ mem_index,
+ s->code_ptr,
+ label_ptr);
+#else
+ {
+ int32_t offset = GUEST_BASE;
+ int base = args[addrlo_idx];
+
+ if (TCG_TARGET_REG_BITS == 64) {
+ /* ??? We assume all operations have left us with register
+ contents that are zero extended. So far this appears to
+ be true. If we want to enforce this, we can either do
+ an explicit zero-extension here, or (if GUEST_BASE == 0)
+ use the ADDR32 prefix. For now, do nothing. */
+
+ if (offset != GUEST_BASE) {
+ tcg_out_movi(s, TCG_TYPE_I64, TCG_REG_L0, GUEST_BASE);
+ tgen_arithr(s, ARITH_ADD + P_REXW, TCG_REG_L0, base);
+ base = TCG_REG_L0;
+ offset = 0;
+ }
+ }
+
+ tcg_out_qemu_st_direct(s, data_reg, data_reg2, base, offset, opc);
+ }
+#endif
+}
+
+#if defined(CONFIG_SOFTMMU)
+/*
+ * Record the context of a call to the out of line helper code for the slow path
+ * for a load or store, so that we can later generate the correct helper code
+ */
+static void add_qemu_ldst_label(TCGContext *s,
+ int is_ld,
+ int opc,
+ int data_reg,
+ int data_reg2,
+ int addrlo_reg,
+ int addrhi_reg,
+ int mem_index,
+ uint8_t *raddr,
+ uint8_t **label_ptr)
+{
+ int idx;
+ TCGLabelQemuLdst *label;
+
+ if (s->nb_qemu_ldst_labels >= TCG_MAX_QEMU_LDST) {
+ tcg_abort();
+ }
+
+ idx = s->nb_qemu_ldst_labels++;
+ label = (TCGLabelQemuLdst *)&s->qemu_ldst_labels[idx];
+ label->is_ld = is_ld;
+ label->opc = opc;
+ label->datalo_reg = data_reg;
+ label->datahi_reg = data_reg2;
+ label->addrlo_reg = addrlo_reg;
+ label->addrhi_reg = addrhi_reg;
+ label->mem_index = mem_index;
+ label->raddr = raddr;
+ label->label_ptr[0] = label_ptr[0];
+ if (TARGET_LONG_BITS > TCG_TARGET_REG_BITS) {
+ label->label_ptr[1] = label_ptr[1];
+ }
+}
+
+/*
+ * Generate code for the slow path for a load at the end of block
+ */
+static void tcg_out_qemu_ld_slow_path(TCGContext *s, TCGLabelQemuLdst *label)
+{
+ int s_bits;
+ int opc = label->opc;
+ int mem_index = label->mem_index;
+#if TCG_TARGET_REG_BITS == 32
+ int stack_adjust;
+ int addrlo_reg = label->addrlo_reg;
+ int addrhi_reg = label->addrhi_reg;
+#endif
+ int data_reg = label->datalo_reg;
+ int data_reg2 = label->datahi_reg;
+ uint8_t *raddr = label->raddr;
+ uint8_t **label_ptr = &label->label_ptr[0];
+
+ s_bits = opc & 3;
+
+ /* resolve label address */
+ *(uint32_t *)label_ptr[0] = (uint32_t)(s->code_ptr - label_ptr[0] - 4);
+ if (TARGET_LONG_BITS > TCG_TARGET_REG_BITS) {
+ *(uint32_t *)label_ptr[1] = (uint32_t)(s->code_ptr - label_ptr[1] - 4);
+ }
+
+#if TCG_TARGET_REG_BITS == 32
+ tcg_out_pushi(s, mem_index);
+ stack_adjust = 4;
+ if (TARGET_LONG_BITS == 64) {
+ tcg_out_push(s, addrhi_reg);
+ stack_adjust += 4;
+ }
+ tcg_out_push(s, addrlo_reg);
+ stack_adjust += 4;
+ tcg_out_push(s, TCG_AREG0);
+ stack_adjust += 4;
+#else
+ /* The first argument is already loaded with addrlo. */
+ tcg_out_movi(s, TCG_TYPE_I32, tcg_target_call_iarg_regs[1],
+ mem_index);
+ /* XXX/FIXME: suboptimal */
+ tcg_out_mov(s, TCG_TYPE_I64, tcg_target_call_iarg_regs[3], TCG_REG_L2);
+ tcg_out_mov(s, TCG_TYPE_I64, tcg_target_call_iarg_regs[2], TCG_REG_L1);
+ tcg_out_mov(s, TCG_TYPE_I64, tcg_target_call_iarg_regs[1], TCG_REG_L0);
+ tcg_out_mov(s, TCG_TYPE_I64, tcg_target_call_iarg_regs[0], TCG_AREG0);
+#endif
+
+ /* Code generation of qemu_ld/st's slow path calling MMU helper
+
+ PRE_PROC ...
+ call MMU helper
+ jmp POST_PROC (2b) : short forward jump <- GETRA()
+ jmp next_code (5b) : dummy long backward jump which is never executed
+ POST_PROC ... : do post-processing <- GETRA() + 7
+ jmp next_code : jump to the code corresponding to next IR of qemu_ld/st
+ */
+
+ tcg_out_calli(s, (tcg_target_long)qemu_ld_helpers[s_bits]);
+
+ /* Jump to post-processing code */
tcg_out8(s, OPC_JMP_short);
- label_ptr[2] = s->code_ptr;
- s->code_ptr++;
+ tcg_out8(s, 5);
+ /* Dummy backward jump having information of fast path'pc for MMU helpers */
+ tcg_out8(s, OPC_JMP_long);
+ *(int32_t *)s->code_ptr = (int32_t)(raddr - s->code_ptr - 4);
+ s->code_ptr += 4;
- /* TLB Miss. */
+#if TCG_TARGET_REG_BITS == 32
+ if (stack_adjust == (TCG_TARGET_REG_BITS / 8)) {
+ /* Pop and discard. This is 2 bytes smaller than the add. */
+ tcg_out_pop(s, TCG_REG_ECX);
+ } else if (stack_adjust != 0) {
+ tcg_out_addi(s, TCG_REG_CALL_STACK, stack_adjust);
+ }
+#endif
- /* label1: */
- *label_ptr[0] = s->code_ptr - label_ptr[0] - 1;
+ switch (opc) {
+ case 0 | 4:
+ tcg_out_ext8s(s, data_reg, TCG_REG_EAX, P_REXW);
+ break;
+ case 1 | 4:
+ tcg_out_ext16s(s, data_reg, TCG_REG_EAX, P_REXW);
+ break;
+ case 0:
+ tcg_out_ext8u(s, data_reg, TCG_REG_EAX);
+ break;
+ case 1:
+ tcg_out_ext16u(s, data_reg, TCG_REG_EAX);
+ break;
+ case 2:
+ tcg_out_mov(s, TCG_TYPE_I32, data_reg, TCG_REG_EAX);
+ break;
+#if TCG_TARGET_REG_BITS == 64
+ case 2 | 4:
+ tcg_out_ext32s(s, data_reg, TCG_REG_EAX);
+ break;
+#endif
+ case 3:
+ if (TCG_TARGET_REG_BITS == 64) {
+ tcg_out_mov(s, TCG_TYPE_I64, data_reg, TCG_REG_RAX);
+ } else if (data_reg == TCG_REG_EDX) {
+ /* xchg %edx, %eax */
+ tcg_out_opc(s, OPC_XCHG_ax_r32 + TCG_REG_EDX, 0, 0, 0);
+ tcg_out_mov(s, TCG_TYPE_I32, data_reg2, TCG_REG_EAX);
+ } else {
+ tcg_out_mov(s, TCG_TYPE_I32, data_reg, TCG_REG_EAX);
+ tcg_out_mov(s, TCG_TYPE_I32, data_reg2, TCG_REG_EDX);
+ }
+ break;
+ default:
+ tcg_abort();
+ }
+
+ /* Jump to the code corresponding to next IR of qemu_st */
+ tcg_out_jmp(s, (tcg_target_long)raddr);
+}
+
+/*
+ * Generate code for the slow path for a store at the end of block
+ */
+static void tcg_out_qemu_st_slow_path(TCGContext *s, TCGLabelQemuLdst *label)
+{
+ int s_bits;
+ int stack_adjust;
+ int opc = label->opc;
+ int mem_index = label->mem_index;
+ int data_reg = label->datalo_reg;
+#if TCG_TARGET_REG_BITS == 32
+ int data_reg2 = label->datahi_reg;
+ int addrlo_reg = label->addrlo_reg;
+ int addrhi_reg = label->addrhi_reg;
+#endif
+ uint8_t *raddr = label->raddr;
+ uint8_t **label_ptr = &label->label_ptr[0];
+
+ s_bits = opc & 3;
+
+ /* resolve label address */
+ *(uint32_t *)label_ptr[0] = (uint32_t)(s->code_ptr - label_ptr[0] - 4);
if (TARGET_LONG_BITS > TCG_TARGET_REG_BITS) {
- *label_ptr[1] = s->code_ptr - label_ptr[1] - 1;
+ *(uint32_t *)label_ptr[1] = (uint32_t)(s->code_ptr - label_ptr[1] - 4);
}
- /* XXX: move that code at the end of the TB */
#if TCG_TARGET_REG_BITS == 32
tcg_out_pushi(s, mem_index);
stack_adjust = 4;
@@ -1417,10 +1551,10 @@ static void tcg_out_qemu_st(TCGContext *s, const TCGArg *args,
tcg_out_push(s, data_reg);
stack_adjust += 4;
if (TARGET_LONG_BITS == 64) {
- tcg_out_push(s, args[addrlo_idx + 1]);
+ tcg_out_push(s, addrhi_reg);
stack_adjust += 4;
}
- tcg_out_push(s, args[addrlo_idx]);
+ tcg_out_push(s, addrlo_reg);
stack_adjust += 4;
tcg_out_push(s, TCG_AREG0);
stack_adjust += 4;
@@ -1436,8 +1570,26 @@ static void tcg_out_qemu_st(TCGContext *s, const TCGArg *args,
tcg_out_mov(s, TCG_TYPE_I64, tcg_target_call_iarg_regs[0], TCG_AREG0);
#endif
+ /* Code generation of qemu_ld/st's slow path calling MMU helper
+
+ PRE_PROC ...
+ call MMU helper
+ jmp POST_PROC (2b) : short forward jump <- GETRA()
+ jmp next_code (5b) : dummy long backward jump which is never executed
+ POST_PROC ... : do post-processing <- GETRA() + 7
+ jmp next_code : jump to the code corresponding to next IR of qemu_ld/st
+ */
+
tcg_out_calli(s, (tcg_target_long)qemu_st_helpers[s_bits]);
+ /* Jump to post-processing code */
+ tcg_out8(s, OPC_JMP_short);
+ tcg_out8(s, 5);
+ /* Dummy backward jump having information of fast path'pc for MMU helpers */
+ tcg_out8(s, OPC_JMP_long);
+ *(int32_t *)s->code_ptr = (int32_t)(raddr - s->code_ptr - 4);
+ s->code_ptr += 4;
+
if (stack_adjust == (TCG_TARGET_REG_BITS / 8)) {
/* Pop and discard. This is 2 bytes smaller than the add. */
tcg_out_pop(s, TCG_REG_ECX);
@@ -1445,32 +1597,29 @@ static void tcg_out_qemu_st(TCGContext *s, const TCGArg *args,
tcg_out_addi(s, TCG_REG_CALL_STACK, stack_adjust);
}
- /* label2: */
- *label_ptr[2] = s->code_ptr - label_ptr[2] - 1;
-#else
- {
- int32_t offset = GUEST_BASE;
- int base = args[addrlo_idx];
-
- if (TCG_TARGET_REG_BITS == 64) {
- /* ??? We assume all operations have left us with register
- contents that are zero extended. So far this appears to
- be true. If we want to enforce this, we can either do
- an explicit zero-extension here, or (if GUEST_BASE == 0)
- use the ADDR32 prefix. For now, do nothing. */
+ /* Jump to the code corresponding to next IR of qemu_st */
+ tcg_out_jmp(s, (tcg_target_long)raddr);
+}
- if (offset != GUEST_BASE) {
- tcg_out_movi(s, TCG_TYPE_I64, TCG_REG_L0, GUEST_BASE);
- tgen_arithr(s, ARITH_ADD + P_REXW, TCG_REG_L0, base);
- base = TCG_REG_L0;
- offset = 0;
- }
+/*
+ * Generate TB finalization at the end of block
+ */
+void tcg_out_tb_finalize(TCGContext *s)
+{
+ int i;
+ TCGLabelQemuLdst *label;
+
+ /* qemu_ld/st slow paths */
+ for (i = 0; i < s->nb_qemu_ldst_labels; i++) {
+ label = (TCGLabelQemuLdst *)&s->qemu_ldst_labels[i];
+ if (label->is_ld) {
+ tcg_out_qemu_ld_slow_path(s, label);
+ } else {
+ tcg_out_qemu_st_slow_path(s, label);
}
-
- tcg_out_qemu_st_direct(s, data_reg, data_reg2, base, offset, opc);
}
-#endif
}
+#endif /* CONFIG_SOFTMMU */
static inline void tcg_out_op(TCGContext *s, TCGOpcode opc,
const TCGArg *args, const int *const_args)
diff --git a/tcg/tcg.c b/tcg/tcg.c
index 32cd0c6..d224f61 100644
--- a/tcg/tcg.c
+++ b/tcg/tcg.c
@@ -303,6 +303,14 @@ void tcg_func_start(TCGContext *s)
gen_opc_ptr = gen_opc_buf;
gen_opparam_ptr = gen_opparam_buf;
+
+#if defined(CONFIG_QEMU_LDST_OPTIMIZATION) && defined(CONFIG_SOFTMMU)
+ /* Initialize qemu_ld/st labels to assist code generation at the end of TB
+ for TLB miss cases at the end of TB */
+ s->qemu_ldst_labels = tcg_malloc(sizeof(TCGLabelQemuLdst) *
+ TCG_MAX_QEMU_LDST);
+ s->nb_qemu_ldst_labels = 0;
+#endif
}
static inline void tcg_temp_alloc(TCGContext *s, int n)
@@ -2164,6 +2172,10 @@ static inline int tcg_gen_code_common(TCGContext *s, uint8_t *gen_code_buf,
#endif
}
the_end:
+#if defined(CONFIG_QEMU_LDST_OPTIMIZATION) && defined(CONFIG_SOFTMMU)
+ /* Generate TB finalization at the end of block */
+ tcg_out_tb_finalize(s);
+#endif
return -1;
}
diff --git a/tcg/tcg.h b/tcg/tcg.h
index 7bafe0e..c930d1a 100644
--- a/tcg/tcg.h
+++ b/tcg/tcg.h
@@ -188,6 +188,24 @@ typedef tcg_target_ulong TCGArg;
are aliases for target_ulong and host pointer sized values respectively.
*/
+#if defined(CONFIG_QEMU_LDST_OPTIMIZATION) && defined(CONFIG_SOFTMMU)
+/* Macros/structures for qemu_ld/st IR code optimization:
+ TCG_MAX_HELPER_LABELS is defined as same as OPC_BUF_SIZE in exec-all.h. */
+#define TCG_MAX_QEMU_LDST 640
+
+typedef struct TCGLabelQemuLdst {
+ int is_ld:1; /* qemu_ld: 1, qemu_st: 0 */
+ int opc:4;
+ int addrlo_reg; /* reg index for low word of guest virtual addr */
+ int addrhi_reg; /* reg index for high word of guest virtual addr */
+ int datalo_reg; /* reg index for low word to be loaded or stored */
+ int datahi_reg; /* reg index for high word to be loaded or stored */
+ int mem_index; /* soft MMU memory index */
+ uint8_t *raddr; /* gen code addr of the next IR of qemu_ld/st IR */
+ uint8_t *label_ptr[2]; /* label pointers to be updated */
+} TCGLabelQemuLdst;
+#endif
+
#ifdef CONFIG_DEBUG_TCG
#define DEBUG_TCGV 1
#endif
@@ -422,6 +440,13 @@ struct TCGContext {
int temps_in_use;
int goto_tb_issue_mask;
#endif
+
+#if defined(CONFIG_QEMU_LDST_OPTIMIZATION) && defined(CONFIG_SOFTMMU)
+ /* labels info for qemu_ld/st IRs
+ The labels help to generate TLB miss case codes at the end of TB */
+ TCGLabelQemuLdst *qemu_ldst_labels;
+ int nb_qemu_ldst_labels;
+#endif
};
extern TCGContext tcg_ctx;
@@ -625,3 +650,8 @@ extern uint8_t code_gen_prologue[];
#endif
void tcg_register_jit(void *buf, size_t buf_size);
+
+#if defined(CONFIG_QEMU_LDST_OPTIMIZATION) && defined(CONFIG_SOFTMMU)
+/* Generate TB finalization at the end of block */
+void tcg_out_tb_finalize(TCGContext *s);
+#endif
--
1.7.5.4
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