MIPS64: Fix BranchF() usage.

src/mips64/macro-assembler-mips64.cc

Index: src/mips64/macro-assembler-mips64.cc
diff --git a/src/mips64/macro-assembler-mips64.cc b/src/mips64/macro-assembler-mips64.cc
index 8dcd9d6c065739600ebaeafbe9f8bb45e042ea50..40c35c0092af5cb3f033e2474eadfde93d8846a8 100644
--- a/src/mips64/macro-assembler-mips64.cc
+++ b/src/mips64/macro-assembler-mips64.cc
@@ -1706,6 +1706,7 @@ void MacroAssembler::Trunc_ul_d(FPURegister fd, Register rs,
   if (result.is_valid()) {
     mov(result, zero_reg);
     Move(kDoubleRegZero, 0.0);
+    // If fd < 0 or unordered, then the conversion fails.
     BranchF(&fail, &fail, lt, fd, kDoubleRegZero);
   }
 
@@ -1715,8 +1716,7 @@ void MacroAssembler::Trunc_ul_d(FPURegister fd, Register rs,
 
   // Test if scratch > fd.
   // If fd < 2^63 we can convert it normally.
-  // If fd is unordered the conversion fails.
-  BranchF(&simple_convert, &fail, lt, fd, scratch);
+  BranchF(&simple_convert, nullptr, lt, fd, scratch);
 
   // First we subtract 2^63 from fd, then trunc it to rs
   // and add 2^63 to rs.
@@ -1733,9 +1733,12 @@ void MacroAssembler::Trunc_ul_d(FPURegister fd, Register rs,
 
   bind(&done);
   if (result.is_valid()) {
-    // Conversion is failed if the result is negative or unordered.
-    BranchF(&fail, &fail, lt, scratch, kDoubleRegZero);
-    li(result, Operand(1));
+    // Conversion is failed if the result is negative.
+    addiu(at, zero_reg, -1);
+    dsrl(at, at, 1);  // Load 2^62.
+    dmfc1(result, scratch);
+    xor_(result, result, at);
+    Slt(result, zero_reg, result);
   }
 
   bind(&fail);
@@ -1761,7 +1764,6 @@ void MacroAssembler::Trunc_ul_s(FPURegister fd, Register rs,
 
   // Test if scratch > fd.
   // If fd < 2^63 we can convert it normally.
-  // // If fd is unordered the conversion fails.
   BranchF32(&simple_convert, nullptr, lt, fd, scratch);
 
   // First we subtract 2^63 from fd, then trunc it to rs
@@ -1780,8 +1782,11 @@ void MacroAssembler::Trunc_ul_s(FPURegister fd, Register rs,
   bind(&done);
   if (result.is_valid()) {
     // Conversion is failed if the result is negative or unordered.
-    BranchF(&fail, &fail, lt, scratch, kDoubleRegZero);
-    li(result, Operand(1));
+    addiu(at, zero_reg, -1);
+    dsrl(at, at, 1);  // Load 2^62.
+    dmfc1(result, scratch);
+    xor_(result, result, at);
+    Slt(result, zero_reg, result);
   }
 
   bind(&fail);