From c15a407eb49d3b26bdbf039816636adb184c276a Mon Sep 17 00:00:00 2001 From: Matt Turner Date: Mon, 2 Nov 2015 10:29:45 -0800 Subject: [PATCH] i965: Make brw_imm_vf4() take 8-bit restricted floats. This partially reverts commit bbf8239f92ecd79431dfa41402e1c85318e7267f. I didn't like that commit to begin with -- computing things at compile time is fine -- but for purposes of verifying that the resulting values are correct, looking up 0x00 and 0x30 in a table is a lot better than evaluating a recursive function. Anyway, by making brw_imm_vf4() take the actual 8-bit restricted floats directly (instead of only integral values that would be converted to restricted float), we can use this function as a replacement for the vector float src_reg/fs_reg constructors. brw_float_to_vf() is not currently an inline function, so it will not be evaluated at compile time. I'll address that in a follow-up patch. Reviewed-by: Emil Velikov Reviewed-by: Kenneth Graunke --- src/mesa/drivers/dri/i965/brw_clip_util.c | 5 ++- src/mesa/drivers/dri/i965/brw_reg.h | 38 +++++------------------ 2 files changed, 11 insertions(+), 32 deletions(-) diff --git a/src/mesa/drivers/dri/i965/brw_clip_util.c b/src/mesa/drivers/dri/i965/brw_clip_util.c index 40ad14402a7..73ba85e2a61 100644 --- a/src/mesa/drivers/dri/i965/brw_clip_util.c +++ b/src/mesa/drivers/dri/i965/brw_clip_util.c @@ -224,7 +224,10 @@ void brw_clip_interp_vertex( struct brw_clip_compile *c, vec1(t_nopersp), brw_imm_f(0)); brw_IF(p, BRW_EXECUTE_1); - brw_MOV(p, t_nopersp, brw_imm_vf4(1, 0, 0, 0)); + brw_MOV(p, t_nopersp, brw_imm_vf4(brw_float_to_vf(1.0), + brw_float_to_vf(0.0), + brw_float_to_vf(0.0), + brw_float_to_vf(0.0))); brw_ENDIF(p); /* Now compute t_nopersp = t_nopersp.y/t_nopersp.x and broadcast it. */ diff --git a/src/mesa/drivers/dri/i965/brw_reg.h b/src/mesa/drivers/dri/i965/brw_reg.h index 3da83b43b5d..e34e7ea0a52 100644 --- a/src/mesa/drivers/dri/i965/brw_reg.h +++ b/src/mesa/drivers/dri/i965/brw_reg.h @@ -43,7 +43,6 @@ #define BRW_REG_H #include -#include "main/imports.h" #include "main/compiler.h" #include "main/macros.h" #include "program/prog_instruction.h" @@ -638,38 +637,15 @@ brw_imm_vf(unsigned v) return imm; } -/** - * Convert an integer into a "restricted" 8-bit float, used in vector - * immediates. The 8-bit floating point format has a sign bit, an - * excess-3 3-bit exponent, and a 4-bit mantissa. All integer values - * from -31 to 31 can be represented exactly. - */ -static inline uint8_t -int_to_float8(int x) -{ - if (x == 0) { - return 0; - } else if (x < 0) { - return 1 << 7 | int_to_float8(-x); - } else { - const unsigned exponent = _mesa_logbase2(x); - const unsigned mantissa = (x - (1 << exponent)) << (4 - exponent); - assert(exponent <= 4); - return (exponent + 3) << 4 | mantissa; - } -} - -/** - * Construct a floating-point packed vector immediate from its integer - * values. \sa int_to_float8() - */ static inline struct brw_reg -brw_imm_vf4(int v0, int v1, int v2, int v3) +brw_imm_vf4(unsigned v0, unsigned v1, unsigned v2, unsigned v3) { - return brw_imm_vf((int_to_float8(v0) << 0) | - (int_to_float8(v1) << 8) | - (int_to_float8(v2) << 16) | - (int_to_float8(v3) << 24)); + struct brw_reg imm = brw_imm_reg(BRW_REGISTER_TYPE_VF); + imm.vstride = BRW_VERTICAL_STRIDE_0; + imm.width = BRW_WIDTH_4; + imm.hstride = BRW_HORIZONTAL_STRIDE_1; + imm.ud = ((v0 << 0) | (v1 << 8) | (v2 << 16) | (v3 << 24)); + return imm; } -- 2.30.2