From 8f887b4252208e60e7e86217ec3b72fb639a4e82 Mon Sep 17 00:00:00 2001
From: Keith Whitwell <keith@tungstengraphics.com>
Date: Thu, 29 May 2008 13:26:01 +0100
Subject: [PATCH] draw: michal's patch for calling powf...  teapot still not
 quite right

---
 src/gallium/auxiliary/draw/draw_vs_aos.c | 46 ++++++++++++++++++++++++
 src/gallium/auxiliary/draw/draw_vs_aos.h |  1 +
 2 files changed, 47 insertions(+)

diff --git a/src/gallium/auxiliary/draw/draw_vs_aos.c b/src/gallium/auxiliary/draw/draw_vs_aos.c
index 55cabb6df9a..725f36b5025 100644
--- a/src/gallium/auxiliary/draw/draw_vs_aos.c
+++ b/src/gallium/auxiliary/draw/draw_vs_aos.c
@@ -1372,11 +1372,20 @@ static boolean emit_MAD( struct aos_compilation *cp, const struct tgsi_full_inst
    return TRUE;
 }
 
+/* A wrapper for powf().
+ * Makes sure it is cdecl and operates on floats.
+ */
+static float PIPE_CDECL _powerf( float x, float y )
+{
+   return powf( x, y );
+}
+
 /* Really not sufficient -- need to check for conditions that could
  * generate inf/nan values, which will slow things down hugely.
  */
 static boolean emit_POW( struct aos_compilation *cp, const struct tgsi_full_instruction *op ) 
 {
+#if 0
    x87_fld_src(cp, &op->FullSrcRegisters[1], 0);  /* a1.x */
    x87_fld_src(cp, &op->FullSrcRegisters[0], 0);	/* a0.x a1.x */
    x87_fyl2x(cp->func);	                                /* a1*log2(a0) */
@@ -1384,6 +1393,42 @@ static boolean emit_POW( struct aos_compilation *cp, const struct tgsi_full_inst
    x87_emit_ex2( cp );		/* 2^(a1*log2(a0)) */
 
    x87_fstp_dest4(cp, &op->FullDstRegisters[0]);
+#else
+   uint i;
+
+   /* For absolute correctness, need to spill/invalidate all XMM regs
+    * too.  
+    */
+   for (i = 0; i < 8; i++) {
+      if (cp->xmm[i].dirty) 
+         spill(cp, i);
+      aos_release_xmm_reg(cp, i);
+   }
+
+   /* Push caller-save (ie scratch) regs.  
+    */
+   x86_cdecl_caller_push_regs( cp->func );
+
+   x86_lea( cp->func, cp->stack_ESP, x86_make_disp(cp->stack_ESP, -8) );
+
+   x87_fld_src( cp, &op->FullSrcRegisters[1], 0 );
+   x87_fstp( cp->func, x86_make_disp( cp->stack_ESP, 4 ) );
+   x87_fld_src( cp, &op->FullSrcRegisters[0], 0 );
+   x87_fstp( cp->func, x86_make_disp( cp->stack_ESP, 0 ) );
+
+   x86_mov_reg_imm( cp->func, cp->tmp_EAX, (unsigned long) _powerf );
+   x86_call( cp->func, cp->tmp_EAX );
+
+   x86_lea( cp->func, cp->stack_ESP, x86_make_disp(cp->stack_ESP, 8) );
+
+   x86_cdecl_caller_pop_regs( cp->func );
+
+   /* Note retval on x87 stack:
+    */
+   cp->func->x87_stack++;
+
+   x87_fstp_dest4( cp, &op->FullDstRegisters[0] );
+#endif
    return TRUE;
 }
 
@@ -1781,6 +1826,7 @@ static boolean build_vertex_program( struct draw_vs_varient_aos_sse *varient,
    cp.machine_EDX   = x86_make_reg(file_REG32, reg_DX);
    cp.count_ESI     = x86_make_reg(file_REG32, reg_SI);
    cp.temp_EBP     = x86_make_reg(file_REG32, reg_BP);
+   cp.stack_ESP = x86_make_reg( file_REG32, reg_SP );
 
    x86_init_func(cp.func);
 
diff --git a/src/gallium/auxiliary/draw/draw_vs_aos.h b/src/gallium/auxiliary/draw/draw_vs_aos.h
index 665b425e684..fb6d43d32e2 100644
--- a/src/gallium/auxiliary/draw/draw_vs_aos.h
+++ b/src/gallium/auxiliary/draw/draw_vs_aos.h
@@ -160,6 +160,7 @@ struct aos_compilation {
    struct x86_reg machine_EDX;
    struct x86_reg count_ESI;    /* decrements to zero */
    struct x86_reg temp_EBP;
+   struct x86_reg stack_ESP;
 };
 
 struct x86_reg aos_get_xmm_reg( struct aos_compilation *cp );
-- 
2.30.2