[llvm-commits] [llvm-gcc-4.2] r56052 - in /llvm-gcc-4.2/trunk/gcc: common.opt llvm-backend.cpp

[Bill Wendling]

Author: void
Date: Wed Sep 10 02:13:05 2008
New Revision: 56052

URL: http://llvm.org/viewvc/llvm-project?rev=56052&view=rev
Log:
Add the -flimited-precision to the front-end. We error out if a value other
than 6, 12, or 18 is supplied.

Modified:
    llvm-gcc-4.2/trunk/gcc/common.opt
    llvm-gcc-4.2/trunk/gcc/llvm-backend.cpp

Modified: llvm-gcc-4.2/trunk/gcc/common.opt
URL: http://llvm.org/viewvc/llvm-project/llvm-gcc-4.2/trunk/gcc/common.opt?rev=56052&r1=56051&r2=56052&view=diff

==============================================================================
--- llvm-gcc-4.2/trunk/gcc/common.opt (original)
+++ llvm-gcc-4.2/trunk/gcc/common.opt Wed Sep 10 02:13:05 2008
@@ -225,6 +225,13 @@
 Common Report Var(emit_llvm_bc)
 Emit LLVM IR to the output file instead of native machine code.
 
+; Calculate log, log2, log10, exp, exp2, pow(10,x) to a limited precision for
+; single-precision floating-point numbers.
+flimited-precision=
+Common RejectNegative Joined UInteger Var(flag_limited_precision) Init(0)
+Calculate the approximate value of logf, log2f, log10f, expf, exp2f, and
+powf(10,x) to the given bit precision.
+
 ; Debug pass manager
 fdebug-pass-structure
 Common Report Var(flag_debug_pass_structure)

Modified: llvm-gcc-4.2/trunk/gcc/llvm-backend.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm-gcc-4.2/trunk/gcc/llvm-backend.cpp?rev=56052&r1=56051&r2=56052&view=diff

==============================================================================
--- llvm-gcc-4.2/trunk/gcc/llvm-backend.cpp (original)
+++ llvm-gcc-4.2/trunk/gcc/llvm-backend.cpp Wed Sep 10 02:13:05 2008
@@ -159,6 +159,19 @@
   // directly from the command line, do so now.  This is mainly for debugging
   // purposes, and shouldn't really be for general use.
   std::vector<std::string> ArgStrings;
+
+  if (flag_limited_precision > 0) {
+    if (flag_limited_precision != 6 &&
+        flag_limited_precision != 12 &&
+        flag_limited_precision != 18) {
+      error ("only 6-, 12-, and 18-bit limited precision values supported.");
+    }
+
+    std::string Arg = "--limit-float-precision=";
+    Arg += utostr(flag_limited_precision);
+    ArgStrings.push_back(Arg);
+  }
+
   if (llvm_optns) {
     std::string Opts = llvm_optns;
     for (std::string Opt = getToken(Opts); !Opt.empty(); Opt = getToken(Opts))