[Mesa-dev] [PATCH] r600g/sb: improve math optimizations

Vadim Girlin vadimgirlin at gmail.com
Fri May 31 05:37:32 PDT 2013


This patch adds support for some math optimizations that are generally
considered unsafe, that's why they are currently disabled for compute
shaders.

GL requirements are less strict, so they are enabled for
for GL shaders by default. In case of any issues with
applications that rely on higher precision than guaranteed by GL,
'sbsafemath' option in R600_DEBUG allows to disable them.

Signed-off-by: Vadim Girlin <vadimgirlin at gmail.com>
---

There are no regressions on evergreen with piglit tests or any
other apps that I tested, with and without llvm backend.
(Issue with Unigine Heaven that I mentioned on #dri-devel
yesterday was in fact caused by my own well-hidden bug, now it's fixed).

Improvements for real apps probably won't be very noticeable in many cases,
but this still might help some apps, e.g. this improves shader2 test
of the fill benchmark in mesa demos.

 src/gallium/drivers/r600/r600_isa.h          |  19 +-
 src/gallium/drivers/r600/r600_pipe.c         |   1 +
 src/gallium/drivers/r600/r600_pipe.h         |   1 +
 src/gallium/drivers/r600/sb/sb_bc.h          |   1 +
 src/gallium/drivers/r600/sb/sb_bc_parser.cpp |   2 +
 src/gallium/drivers/r600/sb/sb_context.cpp   |   1 +
 src/gallium/drivers/r600/sb/sb_core.cpp      |   1 +
 src/gallium/drivers/r600/sb/sb_expr.cpp      | 444 ++++++++++++++++++++++++---
 src/gallium/drivers/r600/sb/sb_expr.h        |   4 +
 src/gallium/drivers/r600/sb/sb_shader.cpp    |   2 +-
 src/gallium/drivers/r600/sb/sb_shader.h      |   2 +
 11 files changed, 431 insertions(+), 47 deletions(-)

diff --git a/src/gallium/drivers/r600/r600_isa.h b/src/gallium/drivers/r600/r600_isa.h
index 8cccc9d..c6bb869 100644
--- a/src/gallium/drivers/r600/r600_isa.h
+++ b/src/gallium/drivers/r600/r600_isa.h
@@ -84,7 +84,8 @@ enum alu_op_flags
 	 * includes MULADDs (considering the MUL part on src0 and src1 only) */
 	AF_M_COMM = (1 << 23),
 
-	/* associative operation ((a op b) op c) == (a op (b op c))  */
+	/* associative operation ((a op b) op c) == (a op (b op c)),
+	 * includes MULADDs (considering the MUL part on src0 and src1 only) */
 	AF_M_ASSOC = (1 << 24),
 
 	AF_PRED_PUSH = (1 << 25),
@@ -373,11 +374,11 @@ static const struct alu_op_info alu_op_table[] = {
 		{"SAD_ACCUM_HI_UINT",         3, {   -1, 0x0F },{      0,     0,  AF_V,  AF_V},  AF_UINT_DST },
 		{"MULADD_UINT24",             3, {   -1, 0x10 },{      0,     0,  AF_V,  AF_V},  AF_UINT_DST | AF_24 },
 		{"LDS_IDX_OP",                3, {   -1, 0x11 },{      0,     0,  AF_V,  AF_V},  0 },
-		{"MULADD",                    3, { 0x10, 0x14 },{  AF_VS, AF_VS, AF_VS, AF_VS},  AF_M_COMM },
-		{"MULADD_M2",                 3, { 0x11, 0x15 },{  AF_VS, AF_VS, AF_VS, AF_VS},  AF_M_COMM },
-		{"MULADD_M4",                 3, { 0x12, 0x16 },{  AF_VS, AF_VS, AF_VS, AF_VS},  AF_M_COMM },
-		{"MULADD_D2",                 3, { 0x13, 0x17 },{  AF_VS, AF_VS, AF_VS, AF_VS},  AF_M_COMM },
-		{"MULADD_IEEE",               3, { 0x14, 0x18 },{  AF_VS, AF_VS, AF_VS, AF_VS},  AF_M_COMM | AF_IEEE },
+		{"MULADD",                    3, { 0x10, 0x14 },{  AF_VS, AF_VS, AF_VS, AF_VS},  AF_M_COMM | AF_M_ASSOC },
+		{"MULADD_M2",                 3, { 0x11, 0x15 },{  AF_VS, AF_VS, AF_VS, AF_VS},  AF_M_COMM | AF_M_ASSOC },
+		{"MULADD_M4",                 3, { 0x12, 0x16 },{  AF_VS, AF_VS, AF_VS, AF_VS},  AF_M_COMM | AF_M_ASSOC },
+		{"MULADD_D2",                 3, { 0x13, 0x17 },{  AF_VS, AF_VS, AF_VS, AF_VS},  AF_M_COMM | AF_M_ASSOC },
+		{"MULADD_IEEE",               3, { 0x14, 0x18 },{  AF_VS, AF_VS, AF_VS, AF_VS},  AF_M_COMM | AF_M_ASSOC | AF_IEEE },
 		{"CNDE",                      3, { 0x18, 0x19 },{  AF_VS, AF_VS, AF_VS, AF_VS},  AF_CMOV | AF_CC_E },
 		{"CNDGT",                     3, { 0x19, 0x1A },{  AF_VS, AF_VS, AF_VS, AF_VS},  AF_CMOV | AF_CC_GT },
 		{"CNDGE",                     3, { 0x1A, 0x1B },{  AF_VS, AF_VS, AF_VS, AF_VS},  AF_CMOV | AF_CC_GE },
@@ -397,9 +398,9 @@ static const struct alu_op_info alu_op_table[] = {
 		{"MUL_LIT_M2",                3, { 0x0D,   -1 },{  AF_VS, AF_VS,     0,     0},  0 },
 		{"MUL_LIT_M4",                3, { 0x0E,   -1 },{  AF_VS, AF_VS,     0,     0},  0 },
 		{"MUL_LIT_D2",                3, { 0x0F,   -1 },{  AF_VS, AF_VS,     0,     0},  0 },
-		{"MULADD_IEEE_M2",            3, { 0x15,   -1 },{  AF_VS, AF_VS,     0,     0},  AF_IEEE },
-		{"MULADD_IEEE_M4",            3, { 0x16,   -1 },{  AF_VS, AF_VS,     0,     0},  AF_IEEE },
-		{"MULADD_IEEE_D2",            3, { 0x17,   -1 },{  AF_VS, AF_VS,     0,     0},  AF_IEEE },
+		{"MULADD_IEEE_M2",            3, { 0x15,   -1 },{  AF_VS, AF_VS,     0,     0},  AF_M_COMM | AF_M_ASSOC | AF_IEEE },
+		{"MULADD_IEEE_M4",            3, { 0x16,   -1 },{  AF_VS, AF_VS,     0,     0},  AF_M_COMM | AF_M_ASSOC | AF_IEEE },
+		{"MULADD_IEEE_D2",            3, { 0x17,   -1 },{  AF_VS, AF_VS,     0,     0},  AF_M_COMM | AF_M_ASSOC | AF_IEEE },
 
 		{"LDS_ADD",                   2, {   -1, 0x0011 },{      0,     0,  AF_V,  AF_V},  AF_LDS },
 		{"LDS_SUB",                   2, {   -1, 0x0111 },{      0,     0,  AF_V,  AF_V},  AF_LDS },
diff --git a/src/gallium/drivers/r600/r600_pipe.c b/src/gallium/drivers/r600/r600_pipe.c
index 71f555b..b69be61 100644
--- a/src/gallium/drivers/r600/r600_pipe.c
+++ b/src/gallium/drivers/r600/r600_pipe.c
@@ -74,6 +74,7 @@ static const struct debug_named_value debug_options[] = {
 	{ "sbdump", DBG_SB_DUMP, "Print IR dumps after some optimization passes" },
 	{ "sbnofallback", DBG_SB_NO_FALLBACK, "Abort on errors instead of fallback" },
 	{ "sbdisasm", DBG_SB_DISASM, "Use sb disassembler for shader dumps" },
+	{ "sbsafemath", DBG_SB_SAFEMATH, "Disable unsafe math optimizations" },
 
 	DEBUG_NAMED_VALUE_END /* must be last */
 };
diff --git a/src/gallium/drivers/r600/r600_pipe.h b/src/gallium/drivers/r600/r600_pipe.h
index 2a81434..51c3483 100644
--- a/src/gallium/drivers/r600/r600_pipe.h
+++ b/src/gallium/drivers/r600/r600_pipe.h
@@ -249,6 +249,7 @@ typedef boolean (*r600g_dma_blit_t)(struct pipe_context *ctx,
 #define DBG_SB_DUMP		(1 << 25)
 #define DBG_SB_NO_FALLBACK	(1 << 26)
 #define DBG_SB_DISASM	(1 << 27)
+#define DBG_SB_SAFEMATH	(1 << 28)
 
 struct r600_tiling_info {
 	unsigned num_channels;
diff --git a/src/gallium/drivers/r600/sb/sb_bc.h b/src/gallium/drivers/r600/sb/sb_bc.h
index 25255a7..224301f 100644
--- a/src/gallium/drivers/r600/sb/sb_bc.h
+++ b/src/gallium/drivers/r600/sb/sb_bc.h
@@ -621,6 +621,7 @@ public:
 
 	static unsigned dry_run;
 	static unsigned no_fallback;
+	static unsigned safe_math;
 
 	static unsigned dskip_start;
 	static unsigned dskip_end;
diff --git a/src/gallium/drivers/r600/sb/sb_bc_parser.cpp b/src/gallium/drivers/r600/sb/sb_bc_parser.cpp
index c2443b8..a7e7128 100644
--- a/src/gallium/drivers/r600/sb/sb_bc_parser.cpp
+++ b/src/gallium/drivers/r600/sb/sb_bc_parser.cpp
@@ -70,6 +70,8 @@ int bc_parser::decode() {
 	}
 
 	sh = new shader(ctx, t, bc->debug_id);
+	sh->safe_math = sb_context::safe_math || (t == TARGET_COMPUTE);
+
 	int r = decode_shader();
 
 	delete dec;
diff --git a/src/gallium/drivers/r600/sb/sb_context.cpp b/src/gallium/drivers/r600/sb/sb_context.cpp
index 9723a84..78b26d5 100644
--- a/src/gallium/drivers/r600/sb/sb_context.cpp
+++ b/src/gallium/drivers/r600/sb/sb_context.cpp
@@ -34,6 +34,7 @@ unsigned sb_context::dump_pass = 0;
 unsigned sb_context::dump_stat = 0;
 unsigned sb_context::dry_run = 0;
 unsigned sb_context::no_fallback = 0;
+unsigned sb_context::safe_math = 0;
 
 unsigned sb_context::dskip_start = 0;
 unsigned sb_context::dskip_end = 0;
diff --git a/src/gallium/drivers/r600/sb/sb_core.cpp b/src/gallium/drivers/r600/sb/sb_core.cpp
index 5b917ac..d907508 100644
--- a/src/gallium/drivers/r600/sb/sb_core.cpp
+++ b/src/gallium/drivers/r600/sb/sb_core.cpp
@@ -63,6 +63,7 @@ sb_context *r600_sb_context_create(struct r600_context *rctx) {
 	sb_context::dump_stat = df & DBG_SB_STAT;
 	sb_context::dry_run = df & DBG_SB_DRY_RUN;
 	sb_context::no_fallback = df & DBG_SB_NO_FALLBACK;
+	sb_context::safe_math = df & DBG_SB_SAFEMATH;
 
 	sb_context::dskip_start = debug_get_num_option("R600_SB_DSKIP_START", 0);
 	sb_context::dskip_end = debug_get_num_option("R600_SB_DSKIP_END", 0);
diff --git a/src/gallium/drivers/r600/sb/sb_expr.cpp b/src/gallium/drivers/r600/sb/sb_expr.cpp
index 053ab2b..5093d7b 100644
--- a/src/gallium/drivers/r600/sb/sb_expr.cpp
+++ b/src/gallium/drivers/r600/sb/sb_expr.cpp
@@ -388,6 +388,18 @@ bool expr_handler::fold_alu_op1(alu_node& n) {
 	assert(v0 && n.dst[0]);
 
 	if (!v0->is_const()) {
+		// handle (MOV -(MOV -x)) => (MOV x)
+		if (n.bc.op == ALU_OP1_MOV && n.bc.src[0].neg && !n.bc.src[1].abs
+				&& v0->def && v0->def->is_alu_op(ALU_OP1_MOV)) {
+			alu_node *sd = static_cast<alu_node*>(v0->def);
+			if (!sd->bc.clamp && !sd->bc.omod && !sd->bc.src[0].abs &&
+					sd->bc.src[0].neg) {
+				n.src[0] = sd->src[0];
+				n.bc.src[0].neg = 0;
+				v0 = n.src[0]->gvalue();
+			}
+		}
+
 		if ((n.bc.op == ALU_OP1_MOV || n.bc.op == ALU_OP1_MOVA_INT ||
 				n.bc.op == ALU_OP1_MOVA_GPR_INT)
 				&& n.bc.clamp == 0 && n.bc.omod == 0
@@ -452,6 +464,258 @@ bool expr_handler::fold_alu_op1(alu_node& n) {
 	return true;
 }
 
+bool expr_handler::fold_mul_add(alu_node *n) {
+
+	bool ieee;
+	value* v0 = n->src[0]->gvalue();
+
+	alu_node *d0 = (v0->def && v0->def->is_alu_inst()) ?
+			static_cast<alu_node*>(v0->def) : NULL;
+
+	if (d0) {
+		if (d0->is_alu_op(ALU_OP2_MUL_IEEE))
+			ieee = true;
+		else if (d0->is_alu_op(ALU_OP2_MUL))
+			ieee = false;
+		else
+			return false;
+
+		if (!d0->bc.src[0].abs && !d0->bc.src[1].abs &&
+				!n->bc.src[1].abs && !n->bc.src[0].abs && !d0->bc.omod &&
+				!d0->bc.clamp && !n->bc.omod &&
+				(!d0->src[0]->is_kcache() || !d0->src[1]->is_kcache() ||
+						!n->src[1]->is_kcache())) {
+
+			bool mul_neg = n->bc.src[0].neg;
+
+			n->src.resize(3);
+			n->bc.set_op(ieee ? ALU_OP3_MULADD_IEEE : ALU_OP3_MULADD);
+			n->src[2] = n->src[1];
+			n->bc.src[2] = n->bc.src[1];
+			n->src[0] = d0->src[0];
+			n->bc.src[0] = d0->bc.src[0];
+			n->src[1] = d0->src[1];
+			n->bc.src[1] = d0->bc.src[1];
+
+			n->bc.src[0].neg ^= mul_neg;
+
+			fold_alu_op3(*n);
+			return true;
+		}
+	}
+
+	value* v1 = n->src[1]->gvalue();
+
+	alu_node *d1 = (v1->def && v1->def->is_alu_inst()) ?
+			static_cast<alu_node*>(v1->def) : NULL;
+
+	if (d1) {
+		if (d1->is_alu_op(ALU_OP2_MUL_IEEE))
+			ieee = true;
+		else if (d1->is_alu_op(ALU_OP2_MUL))
+			ieee = false;
+		else
+			return false;
+
+		if (!d1->bc.src[1].abs && !d1->bc.src[0].abs &&
+				!n->bc.src[0].abs && !n->bc.src[1].abs && !d1->bc.omod &&
+				!d1->bc.clamp && !n->bc.omod &&
+				(!d1->src[0]->is_kcache() || !d1->src[1]->is_kcache() ||
+						!n->src[0]->is_kcache())) {
+
+			bool mul_neg = n->bc.src[1].neg;
+
+			n->src.resize(3);
+			n->bc.set_op(ieee ? ALU_OP3_MULADD_IEEE : ALU_OP3_MULADD);
+			n->src[2] = n->src[0];
+			n->bc.src[2] = n->bc.src[0];
+			n->src[1] = d1->src[1];
+			n->bc.src[1] = d1->bc.src[1];
+			n->src[0] = d1->src[0];
+			n->bc.src[0] = d1->bc.src[0];
+
+			n->bc.src[1].neg ^= mul_neg;
+
+			fold_alu_op3(*n);
+			return true;
+		}
+	}
+
+	return false;
+}
+
+bool expr_handler::eval_const_op(unsigned op, literal &r,
+                                 literal cv0, literal cv1) {
+
+	switch (op) {
+	case ALU_OP2_ADD: r = cv0.f + cv1.f; break;
+	case ALU_OP2_ADDC_UINT:
+		r = (uint32_t)(((uint64_t)cv0.u + cv1.u)>>32); break;
+	case ALU_OP2_ADD_INT: r = cv0.i + cv1.i; break;
+	case ALU_OP2_AND_INT: r = cv0.i & cv1.i; break;
+	case ALU_OP2_ASHR_INT: r = cv0.i >> (cv1.i & 0x1F); break;
+	case ALU_OP2_BFM_INT:
+		r = (((1 << (cv0.i & 0x1F)) - 1) << (cv1.i & 0x1F)); break;
+	case ALU_OP2_LSHL_INT: r = cv0.i << cv1.i; break;
+	case ALU_OP2_LSHR_INT: r = cv0.u >> cv1.u; break;
+	case ALU_OP2_MAX:
+	case ALU_OP2_MAX_DX10: r = cv0.f > cv1.f ? cv0.f : cv1.f; break;
+	case ALU_OP2_MAX_INT: r = cv0.i > cv1.i ? cv0.i : cv1.i; break;
+	case ALU_OP2_MAX_UINT: r = cv0.u > cv1.u ? cv0.u : cv1.u; break;
+	case ALU_OP2_MIN:
+	case ALU_OP2_MIN_DX10: r = cv0.f < cv1.f ? cv0.f : cv1.f; break;
+	case ALU_OP2_MIN_INT: r = cv0.i < cv1.i ? cv0.i : cv1.i; break;
+	case ALU_OP2_MIN_UINT: r = cv0.u < cv1.u ? cv0.u : cv1.u; break;
+	case ALU_OP2_MUL:
+	case ALU_OP2_MUL_IEEE: r = cv0.f * cv1.f; break;
+	case ALU_OP2_MULHI_INT:
+		r = (int32_t)(((int64_t)cv0.u * cv1.u)>>32); break;
+	case ALU_OP2_MULHI_UINT:
+		r = (uint32_t)(((uint64_t)cv0.u * cv1.u)>>32); break;
+	case ALU_OP2_MULLO_INT:
+		r = (int32_t)(((int64_t)cv0.u * cv1.u) & 0xFFFFFFFF); break;
+	case ALU_OP2_MULLO_UINT:
+		r = (uint32_t)(((uint64_t)cv0.u * cv1.u) & 0xFFFFFFFF); break;
+	case ALU_OP2_OR_INT: r = cv0.i | cv1.i; break;
+	case ALU_OP2_SUB_INT: r = cv0.i - cv1.i; break;
+	case ALU_OP2_XOR_INT: r = cv0.i ^ cv1.i; break;
+
+	default:
+		return false;
+	}
+
+	return true;
+}
+
+// fold the chain of associative ops, e.g. (ADD 2, (ADD x, 3)) => (ADD x, 5)
+bool expr_handler::fold_assoc(alu_node *n) {
+
+	alu_node *a = n;
+	literal cr;
+
+	int last_arg = -3;
+
+	unsigned op = n->bc.op;
+	bool allow_neg = false, cur_neg = false;
+
+	switch(op) {
+	case ALU_OP2_ADD:
+	case ALU_OP2_MUL:
+	case ALU_OP2_MUL_IEEE:
+		allow_neg = true;
+		break;
+	case ALU_OP3_MULADD:
+		allow_neg = true;
+		op = ALU_OP2_MUL;
+		break;
+	case ALU_OP3_MULADD_IEEE:
+		allow_neg = true;
+		op = ALU_OP2_MUL_IEEE;
+		break;
+	default:
+		if (n->bc.op_ptr->src_count != 2)
+			return false;
+	}
+
+	// check if we can evaluate the op
+	if (!eval_const_op(op, cr, literal(0), literal(0)))
+		return false;
+
+	while (true) {
+
+		value *v0 = a->src[0]->gvalue();
+		value *v1 = a->src[1]->gvalue();
+
+		last_arg = -2;
+
+		if (v1->is_const()) {
+			literal arg = v1->get_const_value();
+			apply_alu_src_mod(a->bc, 1, arg);
+			if (cur_neg)
+				arg.f = -arg.f;
+
+			if (a == n)
+				cr = arg;
+			else
+				eval_const_op(op, cr, cr, arg);
+
+			if (v0->def) {
+				alu_node *d0 = static_cast<alu_node*>(v0->def);
+				if ((d0->is_alu_op(op) ||
+						(op == ALU_OP2_MUL_IEEE &&
+								d0->is_alu_op(ALU_OP2_MUL))) &&
+						!d0->bc.omod && (!a->bc.src[0].neg || allow_neg)) {
+					cur_neg ^= a->bc.src[0].neg;
+					a = d0;
+					continue;
+				}
+			}
+			last_arg = 0;
+
+		}
+
+		if (v0->is_const()) {
+			literal arg = v0->get_const_value();
+			apply_alu_src_mod(a->bc, 0, arg);
+			if (cur_neg)
+				arg.f = -arg.f;
+
+			if (last_arg == 0) {
+				eval_const_op(op, cr, cr, arg);
+				last_arg = -1;
+				break;
+			}
+
+			if (a == n)
+				cr = arg;
+			else
+				eval_const_op(op, cr, cr, arg);
+
+			if (v1->def) {
+				alu_node *d1 = static_cast<alu_node*>(v1->def);
+				if ((d1->is_alu_op(op) ||
+						(op == ALU_OP2_MUL_IEEE &&
+								d1->is_alu_op(ALU_OP2_MUL))) &&
+						!d1->bc.omod && (!a->bc.src[1].neg || allow_neg)) {
+					cur_neg ^= a->bc.src[1].neg;
+					a = d1;
+					continue;
+				}
+			}
+
+			last_arg = 1;
+		}
+
+		break;
+	};
+
+	if (last_arg == -1) {
+		// result is const
+		apply_alu_dst_mod(n->bc, cr);
+
+		if (n->bc.op == op) {
+			convert_to_mov(*n, sh.get_const_value(cr));
+			fold_alu_op1(*n);
+			return true;
+		} else { // MULADD => ADD
+			n->src[0] = n->src[2];
+			n->bc.src[0] = n->bc.src[2];
+			n->src[1] = sh.get_const_value(cr);
+			memset(&n->bc.src[1], 0, sizeof(bc_alu_src));
+
+			n->src.resize(2);
+			n->bc.set_op(ALU_OP2_ADD);
+		}
+	} else if (last_arg >= 0) {
+		n->src[0] = a->src[last_arg];
+		n->bc.src[0] = a->bc.src[last_arg];
+		n->bc.src[0].neg ^= cur_neg;
+		n->src[1] = sh.get_const_value(cr);
+		memset(&n->bc.src[1], 0, sizeof(bc_alu_src));
+	}
+
+	return false;
+}
 
 bool expr_handler::fold_alu_op2(alu_node& n) {
 
@@ -464,11 +728,53 @@ bool expr_handler::fold_alu_op2(alu_node& n) {
 		return fold_setcc(n);
 	}
 
+	if (!sh.safe_math && (flags & AF_M_ASSOC)) {
+		if (fold_assoc(&n))
+			return true;
+	}
+
 	value* v0 = n.src[0]->gvalue();
 	value* v1 = n.src[1]->gvalue();
 
 	assert(v0 && v1 && n.dst[0]);
 
+	// handle some operations with equal args, e.g. x + x => x * 2
+	if (v0 == v1) {
+		if (n.bc.src[0].neg == n.bc.src[1].neg &&
+				n.bc.src[0].abs == n.bc.src[1].abs) {
+			switch (n.bc.op) {
+			case ALU_OP2_MIN: // (MIN x, x) => (MOV x)
+			case ALU_OP2_MAX:
+				convert_to_mov(n, v0, n.bc.src[0].neg, n.bc.src[0].abs);
+				return fold_alu_op1(n);
+			case ALU_OP2_ADD:  // (ADD x, x) => (MUL x, 2)
+				if (!sh.safe_math) {
+					n.src[1] = sh.get_const_value(2.0f);
+					memset(&n.bc.src[1], 0, sizeof(bc_alu_src));
+					n.bc.set_op(ALU_OP2_MUL);
+					return fold_alu_op2(n);
+				}
+				break;
+			}
+		}
+		if (n.bc.src[0].neg != n.bc.src[1].neg &&
+				n.bc.src[0].abs == n.bc.src[1].abs) {
+			switch (n.bc.op) {
+			case ALU_OP2_ADD:  // (ADD x, -x) => (MOV 0)
+				if (!sh.safe_math) {
+					convert_to_mov(n, sh.get_const_value(literal(0)));
+					return fold_alu_op1(n);
+				}
+				break;
+			}
+		}
+	}
+
+	if (n.bc.op == ALU_OP2_ADD) {
+		if (fold_mul_add(&n))
+			return true;
+	}
+
 	bool isc0 = v0->is_const();
 	bool isc1 = v1->is_const();
 
@@ -488,42 +794,9 @@ bool expr_handler::fold_alu_op2(alu_node& n) {
 	}
 
 	if (isc0 && isc1) {
-		switch (n.bc.op) {
-		case ALU_OP2_ADD: dv = cv0.f + cv1.f; break;
-		case ALU_OP2_ADDC_UINT:
-			dv = (uint32_t)(((uint64_t)cv0.u + cv1.u)>>32); break;
-		case ALU_OP2_ADD_INT: dv = cv0.i + cv1.i; break;
-		case ALU_OP2_AND_INT: dv = cv0.i & cv1.i; break;
-		case ALU_OP2_ASHR_INT: dv = cv0.i >> (cv1.i & 0x1F); break;
-		case ALU_OP2_BFM_INT:
-			dv = (((1 << (cv0.i & 0x1F)) - 1) << (cv1.i & 0x1F)); break;
-		case ALU_OP2_LSHL_INT: dv = cv0.i << cv1.i; break;
-		case ALU_OP2_LSHR_INT: dv = cv0.u >> cv1.u; break;
-		case ALU_OP2_MAX:
-		case ALU_OP2_MAX_DX10: dv = cv0.f > cv1.f ? cv0.f : cv1.f; break;
-		case ALU_OP2_MAX_INT: dv = cv0.i > cv1.i ? cv0.i : cv1.i; break;
-		case ALU_OP2_MAX_UINT: dv = cv0.u > cv1.u ? cv0.u : cv1.u; break;
-		case ALU_OP2_MIN:
-		case ALU_OP2_MIN_DX10: dv = cv0.f < cv1.f ? cv0.f : cv1.f; break;
-		case ALU_OP2_MIN_INT: dv = cv0.i < cv1.i ? cv0.i : cv1.i; break;
-		case ALU_OP2_MIN_UINT: dv = cv0.u < cv1.u ? cv0.u : cv1.u; break;
-		case ALU_OP2_MUL:
-		case ALU_OP2_MUL_IEEE: dv = cv0.f * cv1.f; break;
-		case ALU_OP2_MULHI_INT:
-			dv = (int32_t)(((int64_t)cv0.u * cv1.u)>>32); break;
-		case ALU_OP2_MULHI_UINT:
-			dv = (uint32_t)(((uint64_t)cv0.u * cv1.u)>>32); break;
-		case ALU_OP2_MULLO_INT:
-			dv = (int32_t)(((int64_t)cv0.u * cv1.u) & 0xFFFFFFFF); break;
-		case ALU_OP2_MULLO_UINT:
-			dv = (uint32_t)(((uint64_t)cv0.u * cv1.u) & 0xFFFFFFFF); break;
-		case ALU_OP2_OR_INT: dv = cv0.i | cv1.i; break;
-		case ALU_OP2_SUB_INT: dv = cv0.i - cv1.i; break;
-		case ALU_OP2_XOR_INT: dv = cv0.i ^ cv1.i; break;
 
-		default:
+		if (!eval_const_op(n.bc.op, dv, cv0, cv1))
 			return false;
-		}
 
 	} else { // one source is const
 
@@ -649,6 +922,11 @@ bool expr_handler::fold_alu_op3(alu_node& n) {
 	if (n.src.size() < 3)
 		return false;
 
+	if (!sh.safe_math && (n.bc.op_ptr->flags & AF_M_ASSOC)) {
+		if (fold_assoc(&n))
+			return true;
+	}
+
 	value* v0 = n.src[0]->gvalue();
 	value* v1 = n.src[1]->gvalue();
 	value* v2 = n.src[2]->gvalue();
@@ -698,6 +976,77 @@ bool expr_handler::fold_alu_op3(alu_node& n) {
 		}
 	}
 
+	// handle (MULADD a, x, MUL (x, b)) => (MUL x, ADD (a, b))
+	if (!sh.safe_math && (n.bc.op == ALU_OP3_MULADD ||
+			n.bc.op == ALU_OP3_MULADD_IEEE)) {
+
+		unsigned op = n.bc.op == ALU_OP3_MULADD_IEEE ?
+				ALU_OP2_MUL_IEEE : ALU_OP2_MUL;
+
+		if (!isc2 && v2->def && v2->def->is_alu_op(op)) {
+
+			alu_node *md = static_cast<alu_node*>(v2->def);
+			value *mv0 = md->src[0]->gvalue();
+			value *mv1 = md->src[1]->gvalue();
+
+			int es0 = -1, es1;
+
+			if (v0 == mv0) {
+				es0 = 0;
+				es1 = 0;
+			} else if (v0 == mv1) {
+				es0 = 0;
+				es1 = 1;
+			} else if (v1 == mv0) {
+				es0 = 1;
+				es1 = 0;
+			} else if (v1 == mv1) {
+				es0 = 1;
+				es1 = 1;
+			}
+
+			if (es0 != -1) {
+				value *va0 = es0 == 0 ? v1 : v0;
+				value *va1 = es1 == 0 ? mv1 : mv0;
+
+				alu_node *add = sh.create_alu();
+				add->bc.set_op(ALU_OP2_ADD);
+
+				add->dst.resize(1);
+				add->src.resize(2);
+
+				value *t = sh.create_temp_value();
+				t->def = add;
+				add->dst[0] = t;
+				add->src[0] = va0;
+				add->src[1] = va1;
+				add->bc.src[0] = n.bc.src[!es0];
+				add->bc.src[1] = md->bc.src[!es1];
+
+				add->bc.src[1].neg ^= n.bc.src[2].neg ^
+						(n.bc.src[es0].neg != md->bc.src[es1].neg);
+
+				n.insert_before(add);
+				vt.add_value(t);
+
+				t = t->gvalue();
+
+				if (es0 == 1) {
+					n.src[0] = n.src[1];
+					n.bc.src[0] = n.bc.src[1];
+				}
+
+				n.src[1] = t;
+				memset(&n.bc.src[1], 0, sizeof(bc_alu_src));
+
+				n.src.resize(2);
+
+				n.bc.set_op(op);
+				return fold_alu_op2(n);
+			}
+		}
+	}
+
 	if (!isc0 && !isc1 && !isc2)
 		return false;
 
@@ -727,13 +1076,34 @@ bool expr_handler::fold_alu_op3(alu_node& n) {
 			}
 		}
 
-		if ((isc0 && cv0 == literal(0)) || (isc1 && cv1 == literal(0))) {
-			switch (n.bc.op) {
-			case ALU_OP3_MULADD:
+		if (n.bc.op == ALU_OP3_MULADD) {
+			if ((isc0 && cv0 == literal(0)) || (isc1 && cv1 == literal(0))) {
 				convert_to_mov(n, n.src[2], n.bc.src[2].neg,  n.bc.src[2].abs);
 				return fold_alu_op1(n);
 			}
 		}
+
+		if (n.bc.op == ALU_OP3_MULADD || n.bc.op == ALU_OP3_MULADD_IEEE) {
+			unsigned op = n.bc.op == ALU_OP3_MULADD_IEEE ?
+					ALU_OP2_MUL_IEEE : ALU_OP2_MUL;
+
+			if (isc1 && v0 == v2) {
+				cv1.f += (n.bc.src[2].neg != n.bc.src[0].neg ? -1.0f : 1.0f);
+				n.src[1] = sh.get_const_value(cv1);
+				n.bc.src[1].neg = 0;
+				n.bc.src[1].abs = 0;
+				n.bc.set_op(op);
+				return fold_alu_op2(n);
+			} else if (isc0 && v1 == v2) {
+				cv0.f += (n.bc.src[2].neg != n.bc.src[1].neg ? -1.0f : 1.0f);
+				n.src[0] = sh.get_const_value(cv0);
+				n.bc.src[0].neg = 0;
+				n.bc.src[0].abs = 0;
+				n.bc.set_op(op);
+				return fold_alu_op2(n);
+			}
+		}
+
 		return false;
 	}
 
diff --git a/src/gallium/drivers/r600/sb/sb_expr.h b/src/gallium/drivers/r600/sb/sb_expr.h
index 1b77c8e..f3c7068 100644
--- a/src/gallium/drivers/r600/sb/sb_expr.h
+++ b/src/gallium/drivers/r600/sb/sb_expr.h
@@ -77,6 +77,10 @@ public:
    bool fold_alu_op2(alu_node &n);
    bool fold_alu_op3(alu_node &n);
 
+   bool fold_mul_add(alu_node *n);
+   bool eval_const_op(unsigned op, literal &r, literal cv0, literal cv1);
+   bool fold_assoc(alu_node *n);
+
    static void apply_alu_src_mod(const bc_alu &bc, unsigned src, literal &v);
    static void apply_alu_dst_mod(const bc_alu &bc, literal &v);
 
diff --git a/src/gallium/drivers/r600/sb/sb_shader.cpp b/src/gallium/drivers/r600/sb/sb_shader.cpp
index 4f5ce11..32760ec 100644
--- a/src/gallium/drivers/r600/sb/sb_shader.cpp
+++ b/src/gallium/drivers/r600/sb/sb_shader.cpp
@@ -39,7 +39,7 @@ shader::shader(sb_context &sctx, shader_target t, unsigned id)
   coal(*this), bbs(),
   target(t), vt(ex), ex(*this), root(),
   compute_interferences(),
-  has_alu_predication(), uses_gradients(), ngpr(), nstack() {}
+  has_alu_predication(), uses_gradients(), safe_math(), ngpr(), nstack() {}
 
 bool shader::assign_slot(alu_node* n, alu_node *slots[5]) {
 
diff --git a/src/gallium/drivers/r600/sb/sb_shader.h b/src/gallium/drivers/r600/sb/sb_shader.h
index 5362e39..ca9d29e 100644
--- a/src/gallium/drivers/r600/sb/sb_shader.h
+++ b/src/gallium/drivers/r600/sb/sb_shader.h
@@ -293,6 +293,8 @@ public:
 	bool has_alu_predication;
 	bool uses_gradients;
 
+	bool safe_math;
+
 	unsigned ngpr, nstack;
 
 	shader(sb_context &sctx, shader_target t, unsigned id);
-- 
1.8.2.1



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