diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Target/R600/SIInstructions.td | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/lib/Target/R600/SIInstructions.td b/lib/Target/R600/SIInstructions.td index a5a0dbb711..ba77e6d9ac 100644 --- a/lib/Target/R600/SIInstructions.td +++ b/lib/Target/R600/SIInstructions.td @@ -1688,16 +1688,30 @@ def : Pat < 0 /* ABS */, 1 /* CLAMP */, 0 /* OMOD */, 0 /* NEG */) >; +/********** ================================ **********/ +/********** Floating point absolute/negative **********/ +/********** ================================ **********/ + +// Manipulate the sign bit directly, as e.g. using the source negation modifier +// in V_ADD_F32_e64 $src, 0, [...] does not result in -0.0 for $src == +0.0, +// breaking the piglit *s-floatBitsToInt-neg* tests + +// TODO: Look into not implementing isFNegFree/isFAbsFree for SI, and possibly +// removing these patterns + +def : Pat < + (fneg (fabs f32:$src)), + (V_OR_B32_e32 $src, (V_MOV_B32_e32 0x80000000)) /* Set sign bit */ +>; + def : Pat < (fabs f32:$src), - (V_ADD_F32_e64 $src, (i32 0 /* SRC1 */), - 1 /* ABS */, 0 /* CLAMP */, 0 /* OMOD */, 0 /* NEG */) + (V_AND_B32_e32 $src, (V_MOV_B32_e32 0x7fffffff)) /* Clear sign bit */ >; def : Pat < (fneg f32:$src), - (V_ADD_F32_e64 $src, (i32 0 /* SRC1 */), - 0 /* ABS */, 0 /* CLAMP */, 0 /* OMOD */, 1 /* NEG */) + (V_XOR_B32_e32 $src, (V_MOV_B32_e32 0x80000000)) /* Toggle sign bit */ >; /********** ================== **********/ |