fpudebug

2 files changed, 26 insertions, 2 deletions

diff --git a/hmatrix.cabal b/hmatrix.cabal
index 764198c..10c8173 100644
--- a/hmatrix.cabal
+++ b/hmatrix.cabal
@@ -1,5 +1,5 @@
 Name:               hmatrix
-Version:            0.11.0.3
+Version:            0.11.0.4
 License:            GPL
 License-file:       LICENSE
 Author:             Alberto Ruiz
@@ -87,6 +87,10 @@ flag finit
     description:    Force FPU initialization in foreing calls
     default:        False
 
+flag fpudebug
+    description:    Check FPU stack
+    default:        False
+
 library
 
     Build-Depends:      base >= 4 && < 5,
@@ -170,6 +174,9 @@ library
     if flag(finit)
         cpp-options: -DFINIT
 
+    if flag(fpudebug)
+        cc-options: -DFPUDEBUG
+
     if impl(ghc == 7.0.1)
         cpp-options: -DNONORMVTEST
 
diff --git a/lib/Numeric/LinearAlgebra/LAPACK/lapack-aux.c b/lib/Numeric/LinearAlgebra/LAPACK/lapack-aux.c
index f4ae0f6..77a8847 100644
--- a/lib/Numeric/LinearAlgebra/LAPACK/lapack-aux.c
+++ b/lib/Numeric/LinearAlgebra/LAPACK/lapack-aux.c
@@ -47,7 +47,24 @@
 //---------------------------------------
 void asm_finit() {
 #ifdef i386
-    asm("finit");
+
+    #if FPUDEBUG
+        uint val=0;
+        asm("fstsw"
+        : "=a" (val)
+        : "a"  (val)
+        );
+
+        val = (val%16384)/2048; // bits 13-11
+
+        if (val != 0) {
+            printf("Warning: FPU Stack: %d\n",val);
+            asm("finit");
+        }
+    #else
+        asm("finit");
+    #endif
+
 #endif
 }
 //---------------------------------------